fagnaml

Thanks for the feedback thus far. I call Freightliner about the coolant filter and that tech (yet another one) said I don't have a coolant filter (yay!). I explained my temperature fluctuation and fan behavior to him and his response was "not what he has seen". He did recommend that I call Cummins Customer Care at 1-800-286-6467 to discuss my situation (I hadn't found that phone number yet). The tech I talked to a Cummins told me my ISB engine is "programmed" to operate in the 187 - 207 F temperature range and the fact that the engine temp creeped up to 210-212 F as the fan was going to high speed was not a concern. The fan and cooling system is operating as it should. The tech said max engine temp for the ISB is 225 F. So if the engine temperature control is "programmed" to operating in the 187 - 207 F, I now wonder if I have nothing to worry about ?? I'm still taking the motorhome to Houston Cummins Coach Care next week for coolant change and thermostat change just so I can "check the box" for those routing maintenance items. Also, for the coolant change Freightliner to me to refill with the purple coolant with SCAs as the "probes" installed in the cooling system are for purple color coolant. If red color long life coolant is used the probes may not work with that color. My head is spinning with all of this varying information. I feel like an idiot who knows nothing. Can someone please give me a sanity check??

During lunch I accessed Cummins Power Club to learn of any guidance Cummins provides for the my ISB 6.7L engine. I was surprised to find that in the maintenance service intervals that servicing (changing?) the coolant filter is recommended every six months. Presuming I have a coolant filter, I have to presume it has never been changed and if it is dirty that filter could be causing reduced coolant circulation which could lead to the temperature fluctuation I am experiencing. So, my latest question for the forum is do newer ISB engines have a coolant filter and if "yes" where is the filter located? Here is the link to the Cummins brochure with maintenance intervals for 6.7L ISB engines --> http://files.trypsi.com/cummins/maint_care/2013_ISB67_RVApps.pdf Your thoughts please !!

Thanks for the additional contact info at Freightliner. There is decent air flow when I stand behind the motorhome with the fan is at low speed. When your clutch failed, did you have any air flow when the fan was at low speed? I made an appointment for next Tuesday at Houston Cummins Coach Care for the coolant change that is one year overdue per the owner’s manual. The very knowledgeable shop supervisor at Cummins (Justin McDonald) is also thinking a sticky thermostat based on the symptoms I’ve described. For the coolant change Justin said Cummins will use the “red” long life Fleetguard coolant for my 6.7L, 360 HP ISB engine. He said he doesn’t understand why Freightliner does OEM full with the short life “purple” coolant that requires monitoring of SCAs. Will let the forum know if Cummins finds anyother problems other than the suspect thermostat.

Help me understand how the CAC is the culprit. The CAC was not dirty except for a light coating of dust. After the thorough cleaning it looks brand new. Hence if the CAC is clean how is it causing the engine temp to continuously fluctuate 20-25 F?

Carl -- Bill already provided the "yes" answer to red dyed diesel in terms of needing to use stabilizer and algecide additives. Keep in mind that "red" diesel has higher sulfur content compared to ULSD (i.e. 500 ppm sulfur vs. 15 ppm sulfur in ULSD) and can only be used for off-road use (e.g. farm equipment, rail road engines, etc. without SCRs). Don't allow red dyed diesel anywhere near engines that have SCRs in the exhaust system. The sulfur in red diesel would quickly kill the catalyst in the SCRs.

A quick update. This past Saturday (10/19/19) eldest son and I cleaned the charge air cooler / radiator from both sides even though once we accessed the CAG via the rear bathroom, it only had a fine coating of dust (the "pre-cleaning" photo of the CAG is shown below). We obtained very good water flow both directions and had clear water essentially all of the time (i.e. not enough dirt to discolor the water). . After all of that work, while driving the motorhome back to the storage facility, the engine temperature resumed its near constant 20-25 F fluctuation with the fan going into and out of high speed to lower the engine temp. I called FCCC again late Saturday afternoon and the service tech I spoke to gave me a different answer is that my engine temp should hold relatively constant. I asked him about what could cause the constant fluctuations and he didn't know. I asked about a partially stuck thermostat and his response was thermostats only get stuck in a full open or full closed position. So, thus far I've ruled out a dirty CAG or bad-acting fan clutch as the cause of the temp fluctuations. The coolant (which is the OEM fill "purple" heavy duty coolant with SCA's) test OK per the test strips. I'm still thinking I have a thermostat problem. Only other possibility is the water pump somehow not performing properly? I need the forum's expertise on what to try next. Or do I succumb to taking the motorhome to the Houston Cummins Coach Care.... Thanks for the help! p.s. In my Ventana LE, the bathroom sink is centrally located on the rear wall of the motorhome (with washer / dryer on one side and closet on the other side). Newmar did a really nice design of including an engine access door (hidden behind a cabinet panel) below the bathroom sink cabinet for easy access to clean the CAG. I didn't have to mess with pulling up the floor panel to clean the CAG.

Lyle -- Brett has given excellent advice as usual. The Power Service winterizer/anti-gel additive Brett recommends is in a white bottle and should be available at your favorite Walmart --> https://powerservice.com/psp_product/diesel-fuel-supplement-cetane-boost/ Power Service also makes a biocide additive --> https://powerservice.com/psp_product/bio-kleen-diesel-fuel-biocide/ I also use the Sta-bil brand of diesel fuel stabilizer, in addition to the biocide, when my motorhome sits mostly unused for one or more months to keep the diesel from oxidizing / polymerizing, turning black, forming sludge, etc. --> https://www.goldeagle.com/product/diesel-formula-sta-bil-fuel-stabilizer/ In the Houston area, I've typically had to purchase the biocide and stabilizer at a farm and ranch store (Tractor Supply specifically) as local Walmart's do not carry those products. As the "refinery operations guy" in the forum, I highly recommend using the stabilizer and biocide for any longer term storage of diesel (i.e. more than one month) as diesel will oxidize and bacteria will grow in the presence of oxygen and moisture. Keeping your fuel tank full will help minimize, but not eliminate, air (oxygen) and moisture intrusion into your diesel fuel. Also, even though winter ULSD has a cloud point specification of 15 F (the temperature at which wax crystals start to form) I error on the conservative side and add the winterizer / anti-gel additive when ambient temperatures are forecast to drop below 30 F. This link provides good info on what happens to diesel fuel when stored without these additives --> https://diesel-mate.com/fuel-quality-assurance.html

For the cabinet were we have plates, cups, glasses, wine glasses, etc., we use my mother's old trick from travel trailer days bouncing around in the Snowy Range of Wyoming each summer weekend when I was a young kid a few decades ago -- stuff a bed pillow or two around those dishes. Keeping the wine glasses in one piece is especially important

Quick update on insurance rates. I contacted FMCA RV Insurance and received the following annual premiume quotes based on $170,000 motorhome value: Progressive RV = $2,100 Nationwide / Allied = $2,280 Safeco = $2,610 My current Progressive policy with is $3,400 annual premium is through Progressive Direct (their on-line system) and not through Progressive RV for which FMCA RV Insurance is an agent. The nice customer service rep for Progressive Direct said that their high volume policies (i.e. automobiles, homeowner, etc.) premiums are often a tad lower than rates offered by agents. However, for "specialty" insurance such as RVs the Progressive Direct rate is usually somewhat higher than agent rates. The customer service rep was shocked at a $1,300 difference between the on-line Progressive Direct policy and the agent provided Progressive RV policy. Needless to say I'm moving from Progressive Direct to FMCA RV Insurance and a Progressive RV policy. Until now I thought Progressive was Progressive was Progressive...…..

Brett -- FCCC told me late yesterday that I have a Horton fan clutch part # 9908044. That clutch per the Horton website is a VMaster Directly Controlled clutch that is controlled by the engine control module (ECM as FCCC called it). Here are links to info about this type of fan clutch: Fan Clutch details --> https://catalog.hortonww.com/part-details.html?service_no=9904088&measurementSystem=imperial Fan Clutch brochure --> https://www.hortonww.com/assets/documents/horton-productsheet-22837-c-vs-directly-controlled.pdf The brochure has verbiage and charts that describe quite well my experience the last two weekends driving to/from LSU i.e. no change in engine speed (1800 RPM at 65 mph driving speed) while the fan speed increased / decreased to hold engine temperature in a 190 - 210 F range. Per the Horton website, this type of variable speed clutch has been available for use for motorhomes with ISB and ISL engines with rear cooling since 2007. It would be interesting to learn if other forum members have this type of Horton fan clutch. This coming weekend I still will do a more thorough look at my charge air cooler to assure it is clean.

rcieslak67 -- What is the ag, value and model of your Holiday Rambler? Reason for asking is I just received my annual renewal notice from Progressive for my 2016 Newmar Ventana LE 4037 and it was a shocking $3,400 ! This is the first full year premium notice from Progressive since I purchased the Ventana LE a few months ago (I only had to pay an incremental amount to cover the last three months). The current value of my Ventana LE is $165,000. The $3,400 premium is more than the annual premium for my home which has a value three times that of motorhome. I submitted a quote request to FMCA Insurance to see if they can offer a better price......

Brett -- FCCC told me I have a Horton fan clutch. Which model number they did not say and silly me did not ask. I will quiz FCCC about clutch model number. Any comments about the photo of my charge air cooler?

As a follow-up to my original post, below is the e-mail response from FCCC Customer Service about my engine cooling system operating "normally". Also, last week I looked at my charge air cooler following Brett's guidance and found it to look almost new for what I could see without removing the fan shroud (I couldn't quite see the furthest corners of the CAC). I've attached a photo of the charge air cooler (as best that could be laying under the fan and without removing the shroud). Basically what I think I've learned is FCCC designed the cooling system to include a variable speed fan and that my 20-25 F of engine temperature fluctuation is "per design". The FCCC website briefly describes the "automatic variable speed fan" for rear mounted radiators on XCR chassis such as mine --> https://www.fcccrv.com/chassis/xc/engines/#xc-cummins-engines Any comments from the forum about what I've learned in the last week? ============================================================================ Mike, What you have described is normal operation of the cooling system. Sincerely, Justin Pope FCCC Representative --------------------------------------------------------------------------------------------------------------------------------------- 2019-10-14 12:35:45 Fagnant, Michael L. I have a “new to me” 2016 Newmar Ventana LE (VIN# 4UZACHDT8GCHJ1970) that I’ve enjoyed the last two weekends for LSU football outings. It is built on an XCR chassis. The coach is equipped with a 360 HP Cummins 6.7L ISB engine and Allison 3000MH transmission. While driving the motorhome round trip between Houston and Baton Rouge both weekends, the engine temperature would continually fluctuate from ~187 F to ~210 F despite a 20 F difference in ambient air temperature (95 F two weeks ago, 75 F this past weekend). As the engine temperature reached ~210 F, I could hear the cooling fan “kick into” high speed. When the engine temperature cooled off to ~187 F and the fan went to a low speed. The engine temperature would then rise during the next few minutes until reaching ~210 F again at which time the fan went into high speed. This temperature fluctuation cycle continued constantly. Prior to owning this Newmar Ventana LE, I owned a 2007 Damon Astoria that, like the Ventana, was built on an XCR chassis. The Astoria was a somewhat smaller motorhome and thus was equipped with a 300 HP Cummins 5.9L ISB engine and Allison 2500MH transmission. While driving the Astoria to/from Baton Rouge for the last five years, the engine temperature held constant at ~195 F. It didn’t have the large 20 – 25 F temperature fluctuation that I’m experiencing with the Ventana LE. Is the 20-25 F engine temperature fluctuation experienced the last two weekends “normal operation” or do I have a cooling system problem such as a bad thermostat? Should the engine temperature be relatively constant as was my experience with the 2007 Damon Astoria? Thanks for your help and advice. Mike Fagnant

As usual the responses are very informative!! The "thermostat responses" make me question the type of thermostat I have in my ISB engine. I'd presume a 180 - 190 F thermostat?? Presuming I have a 180-190 F thermostat I then wonder why, if the thermostat is wide open, did the engine temp climb to 210 F driving on a flat I-10 between Baton Rouge and Houston and the fan had to go into high speed to keep cool off the engine?? Jim S. -- What other "symptoms" did you have (in addition to the low to high temperature fluctuations that I have) to prompt your clutch replacements? . Reason for asking is my experience with "high school era" older pickups was a clutch replacement was needed because the fan would not engage and the engine overheated (those clutches were the thermal spring type that when they failed the clutch would not grab the engine shaft). Also, the FCCC tech I spoke to yesterday told me I have a Horton brand clutch. Brett -- You very often coach all of us to check that the charge air cooler is clean. When I purchased my Ventana LE from NIRV in Dallas this past April I asked them if the charge air cooler needed cleaning -- they said no. If the charge air cooler is dirty, could that be a reason the engine temperature will not hold at ~190 F with a wide open thermostat? I have another LSU football adventure in Baton Rouge this coming weekend (10/11-13/19) with #7 Florida visiting # 5 LSU. It will be interesting to see what my engine temps do with 75 F ambient temps behind a much welcomed cold front.

Brett -- As always your advice is most welcome. Using the link you provided I found the FCCC spec sheet for the Ventana LE which is essentially the same as the Ventana info you provided --> https://www.fcccrv.com/wp-content/uploads/oem_pdfs/Newmar/2016 Newmar Ventana LE Spec Sheet.pdf I failed to mention in my original post that as I do every LSU football weekend I was towing my 2016 Jeep Wrangler Unlimited Sahara. I called the FCCC "24/7 Direct" customer service phone number and was promptly routed to a technician by the name of Chris. I explained my experiences to Chris (who sounded older in age and quite experienced) who advised the cooling system for my Ventana LE was performing as it should with the fan moving to high speed at 210 - 212 F and returning to low speed at 190-192 F and repeating the cycle as needed. Chris said FCCC has received numerous calls about this temperature fluctuation for Ventana LE's the last few years. Whether he should have or not, Chris stated that his personal opinion is the 360 HP, 6.7L ISB engine is somewhat undersized for my Ventana LE 4037 model especially during hot weather and climbing long hills. He said Newmar / FCCC agreed on using the ISB engine instead of a larger engine to help hold the cost differential between the "entry level" Ventana LE and the "next step up" Ventana. My 2016 Ventana LE has an empty weight of 29,700 lbs, max GVWR of 36,400 lbs. and a max GCWR of 41,400 lbs --> https://library.rvusa.com/brochure/2016VentanaLEBrochure.pdf For an LSU weekend, I carry a full tank of water (830 lbs), full 32 gallon propane tank (135 lbs), three plastic tables, umbrella type camping chairs, small charcoal grill, food, drinks, ice, the wife & me. All that "stuff" is under 2,000 lbs. thus well within the 6,700 lbs of "rated" cargo capacity. Combined weight (calculated) is ~35,700 lbs. which is 5,700 lbs. under the GCWR. Next trip I will have the coach and Jeep weighed to confirm my calculated combined weight. Presuming the combined weight is circa 36,000 lbs. would you agree with Chris at FCCC that a 360 HP ISB engine is a bit undersized?

Jim -- Please share the "symptoms" you experienced with your Horton fan clutch so I can compare/contrast my experiences from yesterday.

Ross -- Sorry, I should have provided chassis and engine info for my 2016 Ventana LE 4037 (which should be visible in my signature block). The chassis is a Freightliner XCR with a 6.7L, 360 HP Cummins ISB engine and Allison MH3000 transmission. The coolant is "original fill" Shell Rotella Fully Formulated with SCAs (purple color coolant) which, per test strips, was in good condition when I purchased the motorhome six months ago. Here is a link to coolant info --> http://shop.sclubricants.com/rotella-fully-formulated-antifreeze-5050 I don't recall seeing this engine temperature fluctuation while driving my previous motorhome unless while climbing a hill or large bridge. The engine temp fluctuation I experienced yesterday is on I-10 which except for a few bridges is very flat.

This past weekend (10/5-7/19) in Baton Rouge for the LSU - Utah State game was brutally hot for the first weekend of October - 97 F ambient temperature with 105 F heat index !! While driving from Baton Rouge to Houston yesterday (Sunday), the engine temperature was fluctuating from 192 F to 210. I saw this fluctuation only because I had my dashboard read-out looking at engine and transmission temps rather than my customary trip and leg fuel mileage read-outs. As I paid closer attention to the engine temp, when the temp reached 210 F I could hear (I think) the radiator fan engage / go into a higher speed and then disengage/slow down when the temp reached 192 F. This fluctuation was continuous during the five hour drive. I don't know if this temperature fluctuation was occurring on my drive to Baton Rouge Friday because my focus was on horrible traffic conditions and I didn't have the dash board read-out set to temperatures. Engine RPM did not change (stayed at 1800) as the engine temp fluctuated and the fan engaged/disengaged. Speed control was steady at 65 mph (my comfortable max speed). This weekend was the first time driving my new to me Newmar Ventana LE in extremely hot weather. Is this 18 F temperature fluctuation "normal" or is it the sign of a problem brewing? Thanks for the help!

During our journeys to Baton Rouge for LSU football games, we spend Thursday afternoon/evening at the A+ RV Park in Sulphur, LA so we can visit youngest son and his family and prep for LSU boon-docking before continuing the drive to BR on Friday mornings. Our first LSU weekend of the year was ten days ago (9/16-19/19). This was the first time we've had a chance to use our new-to-us Ventana LE since a long July 4 weekend. After hooking up water at the A+, I turned-on the cold water side of kitchen faucet and as it started to "spurt and sputter" as air was pushed out of the water line, out came an extremely strong sour / sulfur odor which was bad enough for the propane detector to alarm (propane detectors sense mercaptan odorants in the propane). I then opened cold water sides of both bathroom faucets and had the same stench come out. There was no odor in the water at the the RV park faucet. The only thing I hadn't opened was the permanently mounted in-line Flo Pur brand water filter in the wet bay (http://www.flowpur.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=FP&Product_Code=POE12GHGACB&Category_Code=RVF) When I opened that filter, I found the basic, carbon cartridge to have a horrible sulfur / stagnant water stench! It quickly got thrown into the trash !! Never having this type of filter before, I didn't know nor think that the filter "housing" would hold water and in doing so, the water could become stagnant/sour. My questions to forum members that have my type of water filter are: 1) When you place your coach in storage for several weeks, do you open the filter and dump water from the filter? 2) After dumping water from the filter, do you remove the cartridge, let it dry, and re-use at the next outing? 3) Would the "hose" filter I used with my previous motorhome and travel trailer be a better choice (those filters never went "sour") --> https://www.walmart.com/ip/Camco-40043-TastePURE-Inline-Water-Filter-with-Flexible-Hose-Protector-Greatly-Reduces-Bad-Taste-Odors-Chlorine-and-Sediment-in-Drinking-Water/14504321?sourceid=csebr03a56c93d3ac5c4940bc0d99500c5c7153&wmlspartner=bizratecom&affcmpid=1116078100&tmode=0000&veh=cse&szredirectid=15693638396709632783510090301008005 Thanks for your thoughts and advice!

Quick update. The “all in” price for my six new Hankook AH37, 275R70/22.5 tires was $2,380. I’m extremely pleased with the service from Southern Tire Mart in Katy, TX and with FMCA’s discount pricing program with Hankook. The significant cost savings for my new tires is well worth the cost of an FMCA membership!

Let the "Refiner" in the group opine. Manufacturing Renewable Diesel from new / used vegetable oils or animal fats has been in place for over a decade at refineries owned by most major oil companies. This 2007 presentation from ConocoPhillips describes how vegetable oils and/or animal fats are "co-processed" with conventional diesel from crude oil to produce an outstanding quality, non-Biodiesel, product --> https://www.energy.gov/sites/prod/files/2014/03/f9/deer07_cornforth.pdf This co-processing is done in a refinery process unit know as a Hydrotreater which is decades old technology. Advancements in Hydrotreater catalyst technology now allows vegetable oils / animal fats to be process "neat" in a Hydrotreater type unit which is the business venture in the Valero press release. Most major oil companies are partnering with Renewable Diesel companies to build new renewable diesel "refineries" across the U.S. to meet EPA regulations for renewable fuels use. Those renewable diesel "refineries" will start operation during the next couple of years. The good news about Renewable Diesel is it is very similar to conventional diesel from crude oil with the exception that Renewable Diesel is more paraffinic (higher Cetane Rating , somewhat waxier) which is why major oil companies are investing in Renewable Diesel manufacturing. Biodiesel is an "ester" product which contains oxygen. Esters are good solvents which causes a lot of concern for pipelines and storage tanks (loosen metal scale). Because of the oxygen content in esters, they degrade, turn black, etc. Due to these reasons, major oil companies shy away from Biodiesel.

After crawling underneath the engine this past weekend I found the problem with my check engine light and new Fleet Guard filter-separator. The "plug" for the water sensor was inserted into the "receptacle" of the water sensor but was not in contact with the "pins" of the sensor. Look closer, the "plug" is not compatible with the Fleet Guard sensor i.e. the pins in the sensor are "centered" while the holes in the plug are off-center. The Lube Zone oil change business in Brookshire, TX simply stuck the plug into the sensor receptacle but did not check the sensor pins and plug made contact. Lucky for me, Lube Zone gave me the bowl from the bottom of the old filter-separator which has the original sensor intact. Houston Freightliner, using my VIN, was able to determine the OEM filter-separator used when the chassis was manufactured, a Rancor-Parker brand filter-separator, which they had in stock. After an hour round-trip to/from Houston Freightliner I now have a filter-separator that is compatible with the original bowl section which I will install this evening. The learning for me is don't expect the sensor plug to always be compatible with the sensor on the bottom of every brand of filter-separator ! I'm curious if other owners have had this same issue with their filter-separators? For reference here are links to my OEM filter-separator and bottom bowl. Filter-separator --> https://www.amazon.com/Racor-S3226T/dp/B002MBUKFA/ref=sr_1_1?keywords=racor+s3226t+filter&qid=1568051783&s=gateway&sr=8-1 Bottom bowl --> note that the bowl only comes with a port for a sensor! --> https://www.amazon.com/iFJF-WF10137-Separator-Systems-33630-33812-33813-33774/dp/B07KR29V16/ref=sr_1_fkmr1_1?keywords=racor+bowl+for+s3226t+filter&qid=1568050336&s=gateway&sr=8-1-fkmr1

cbdeajr -- Two weeks ago I purchased a new set of Hankook AH37 275/75R22.5 tires for my motorhome to replace five year old OEM Michelin XZE2+ tires that had some sidewall cracking. I utilized FMCA's tire purchase program with Hankook which lowered the price per tire from $650 list price to only $365 per tire including federal excise tax. I purchased the tires from Southern Tire Mart near my home in Houston. I drove round trip Houston - Baton Rouge this past weekend and the Hankooks rode and handled as well as the Michelins. Like you I drive my motorhome less than 5,000 miles per year meaning my tire will age-out much quicker than they will wear-out. For motorhome owners like us, the Sales Manager recommends "Tier II" tires like Hankook, Yohahoma, etc. For long-haul truckers and motorhome owners that will drive 30,000 miles a year or more, then he would recommend Tier I tires like Michelin, Continental and Bridgestone to provide best tread life possible. Thus far with a whopping 500 miles of use I'm very pleased with my Hankook tires.

Shane -- Four months ago I purchased my Ventana LE from National Indoor RV in Lewisville, TX which was on consignment to them. NIRV in Lewisville is a large Newmar dealer. They gave a me trade-in offer for my 2007 Damon Astoria that was comparable to the trade-in offer I received from PPL Motorhomes in Houston. Given the age of the Damon, NIRV already new they would sell the Damon to a wholesaler (which turned out to be I-35 RV Supercenter in Denton, TX). The "trade-in" inspection by NIRV was a relatively short 45 minute walk-through by their PDI Manager at no cost. The Kimberly you met at NIRV was my sales associate. She (and everyone else at NIRV) provided exceptional customer service throughout our purchase experience and has remained in contact since the purchase. A nice aspect of NIRV is if repair / warranty work is needed, they have a on-site RV park with 20 (+/-) spots that have 50 amp power and water service (no sewer hook up at each site but they do have dump stations) for customers who don't live in the greater Dallas area. I wish NIRV had a location in Houston as the Newmar dealer in Houston is Holiday World which in my opinion is many magnitudes below NIRV in customer service.

Thanks for the prompt and informative replies! In addition to your great thoughts, I was able to contact a mobile diesel engine mechanic who serves the greater west Houston area. He stated that simply disconnecting the sensor from the bottom of the filter-separator can "throw a code". He also gave an identical response as Herman in that the connector for the sensor on the bottom of the filter-separator may not have good contact. That mechanic said his first approach would be to disconnect then reconnect the engine batteries which can often clear a check engine code. If that doesn't work then crawl underneath the engine area and check the sensor connection. If neither of those actions clears the code, then he or a repair shop need to determine what the fault code is. I'll disconnect the batteries this weekend an let the forum know if this action was successful to clear the check engine light. Bill - With regards to your comment about a filter-separator with a bowel, the OEM Fleet Guard filter-separator is bowel-less (filter number FS-1065). Wherever the previous owner had the engine serviced chose to install the Alliance brand filter-separator that had a bowel. The filter-separator is only visible when crawling under the motorhome which I would very rarely do. For motorhomes such as mine that has very limited visibility of the engine, do owners spend much time under the engine to "look at stuff" ? I'll admit that I rely on and trust "my" engine mechanic at RV Masters here in Houston to a good inspection of the engine, charge air cooler, etc. when I take my motorhome to them. As an FYI for the forum that all you probably already know, Cummins has a "Shop Cummins" website that provides a list of filters for each type of Cummins engine. This is the web page for my Cummins ISB 6.7 L engine --> https://shopcummins.com/collections/fleetguard-filters/isb6-7 This web page shows all of the types of filters that could be used on an ISB engine. To get the "exact" filters used on a specific engine, I learned that by providing Cummins Filtration with the engine serial number, Cummins then can provide the OEM filter numbers. Finally, a personal frustration thought. Silly me presumed that just because my "new to me" Newmar was my second motorhome that I knew everything I needed to know about motorhomes. There are enough differences between a 2016 Newmar Ventana LE and my previous 2007 Damon Astoria that I've regressed in my Motorhome 101 class. Both are diesel pushers built on an Freightliner XCR chassis. The Astoria was "simple" from a 12 volt system perspective (only had a converter and no Magnum power control panel), had a pre-DEF ISB engine, no permanent satellite system with Dish Network stuff to learn, etc. Am I alone in feeling that all that has been learned is not enough when purchasing a motorhome that is 12 years newer than the previous motorhome??