mweiner Report post Posted July 7, 2017 Unlike conventional gas engines, diesel engines have been known for going beyond 350,000 to 500,000 miles and sometimes even further... PLUS, when factoring values on NADA, (National Automobile Dealers Association), they tell you that mileage is only to be used for consideration with gas engines only.... SO, how many of you with diesel engines have exceeded 250,000 and what's your experience been with repairs, maintenance, performance, and oil consumption? At what mileage did you consider the diesel engine to be "broken in" and running at top condition? And, what would you consider the top RPM range for cruising? My 3 litre V6 Mercedes Benz Sprinter goes about 2,500 at 60 or 65 MPH.... Share this post Link to post Share on other sites
wolfe10 Report post Posted July 7, 2017 Going to be a lot of "apples and oranges" comparisons here. Your 3 liter MB diesel has little resemblance to the diesels found in most Class A motorhomes. The Class A diesels are all in-line 6 cylinders with displacement from 6.7 to 15 liters. The longer the stroke the lower the RPM at which maximum torque is generated, the lower the RPM for maximum HP and the lower the RPM for governed RPM. And, yes, the larger of these large diesels are the same as in OTR trucks that often go over a million miles before in-frame overhauls. Sure, they can fail, but for most RV's, the coach will wear out long before the engine. Same goes for the Allison transmission. Most failures are due to neglect or driver abuse. This takes nothing away from the excellent drive train in your Sprinter-based RV, but they ARE different. Share this post Link to post Share on other sites
mweiner Report post Posted July 7, 2017 "This takes nothing away from the excellent drive train in your Sprinter-based RV, but they ARE different." Thanks for your reply.... Of course, they're completely different in scale.... and I imagine that the large 6.7 Cummins Diesel engines turn at a lower RPM.. and also consume more fuel, BUT, recently on a trip back through the local mountains, I noticed that climbing to 5,000 feet the 3 litre Diesel was hardly breathing hard compared to my Subaru Outback Limited CVT with the 2.5 that had to run at nearly twice the RPMs to keep up on the hill climb that I did months earlier pulling a 1,000 pound teardrop trailer. Don't really know what transmission Mercedes Benz uses in the Sprinter EXCEPT that they claim it's "heavy duty".... It is pretty smooth..and it has selectable speeds right on the gear shifter. I don't use that for acceleration.. only to shift down to slow down on grades... For most instances, I just gradually accelerate fast enough and keep the RPMs as low as possible... I'm not sure I'll go another 1,000,000 miles even though some engines might (LOL), we'll see... BUT, it appears that mileage on Diesel vehicles in general is LESS of a factor than your typical gasoline engines... Correct? I would be very pleased if the Mercedes Benz Sprinter had the capability to go 350,000 miles.... If you know anything about who makes the MB transmission, maybe it's an in-house product, let me know... Thanks, ---Mark Share this post Link to post Share on other sites
manholt Report post Posted July 8, 2017 I don't mean this as a put down, but you can get far better answers from Roadtrek Tech Department than from most of us. I think your transmission is by Daimler and you should have no problem reaching 350,000 miles on your unit. Share this post Link to post Share on other sites
mweiner Report post Posted July 8, 2017 Carl, no problem Yes, I can certainly call Roadtrek when it's a Roadtrek issue. I suspect that you're correct...it's likely a Mercedes Benz transmission in house unit? Just got an appointment tomorrow for the Takata air bag replacement on the driver's side... I'll ask them about the transmission. I appreciate your honest response of not knowing.. but, I was kinda hoping that someone on the FMCA forum does know the answer? Maybe, these coaches are not that ubiquitous here on the FMCA? I noticed that there was a Roadtrek discussion, but, that was several years ago.. maybe these people have moved on? Share this post Link to post Share on other sites
wolfe10 Report post Posted July 8, 2017 Here is a link to the very active Roadtrek FMCA Chapter: http://www.roadtrekchapter.org Share this post Link to post Share on other sites
mweiner Report post Posted July 8, 2017 Thank you, I'll check it out. Share this post Link to post Share on other sites
mweiner Report post Posted July 8, 2017 Hi Brett, Looked at the Roadtrek International Link http://www.roadtrekchapter.org/ BUT, is there a Southern California chapter??? A lot of these places are pretty far away... geographically not good. Share this post Link to post Share on other sites
manholt Report post Posted July 8, 2017 Ask the Roadtrek Chapter for local chapter info! Share this post Link to post Share on other sites
wildebill308 Report post Posted July 8, 2017 Start a chapter in your area. Bill Share this post Link to post Share on other sites
wajames Report post Posted July 8, 2017 (edited) Roadtrek chapter comes to our Western Area Rally in Indio every year - and they are well represented. http://www.roadtrekchapter.org/region9/ Edited July 8, 2017 by wajames Added region 9 link Share this post Link to post Share on other sites