XZA3 275/80R22.5 Vs. XZE

[rga48]

I recently replaced my original XZA3 275/80R22.5 with XZE's. I can not tell you how much safer I feel! I feel that the XZA3 contributed to a severe under-steer problem. This was most noticeable on a downhill turn to the right with the road slopping right to left. The coach would change a whole lane before I could comfortably get it back under control. This provided many heart stopping moments especially for an unfortunate couple on a motorcycle. I originally thought it was my air leveling system and had the senors checked but they were found to be working properly. Now that I have changed tires the problem is gone. The only issue I had was that my 90 psi rear tire pressure (based on four corner weight) was too soft and was causing rear tire sidewall to flex in heavy crosswinds. I increased pressure to 100 psi and solved the problem.

[mandalay40f]

I recently replaced my original XZA3 275/80R22.5 with XZE's. I can not tell you how much safer I feel! I feel that the XZA3 contributed to a severe under-steer problem. This was most noticeable on a downhill turn to the right with the road slopping right to left. The coach would change a whole lane before I could comfortably get it back under control. This provided many heart stopping moments especially for an unfortunate couple on a motorcycle. I originally thought it was my air leveling system and had the senors checked but they were found to be working properly. Now that I have changed tires the problem is gone. The only issue I had was that my 90 psi rear tire pressure (based on four corner weight) was too soft and was causing rear tire sidewall to flex in heavy crosswinds. I increased pressure to 100 psi and solved the problem.

Was the XZA3 Tires original with your 2006 Allegro Bus? I have a 2007 Mandalay (XC chassis with ZF IFS front end) that was in production in 2006 and came with the same tires. I have 36K and starting year 7 with side wall cracks showing up. Time to change tires. I have experienced the same under steer issues with downhill curves. Increased tire psi to 110F & 100R with some improvement but still not comfortable at certain times. I'm looking at the XZE type and would like to know how the ride is with them vs the XZA3's? Another thought could the under steer be caused by downhill roll on rear tires tail swing in the curve? Always have a 2004 Tahoe toad attached.

[dickandlois]

Regarding the XZE tires, I notice less wandering using them on the front. They are more of a truck tire and have a stiffer sidewall.

My total coach weight is less then yours so I can not speak for how they would work for you.

We do not see any difference in the ride with them though.

Rich.

[mandalay40f]

Rich, Thanks for the reply. To be comparing apples to apples. Just curious if your coach has the ZF-IFS front axle with 14,600# load capacity. My GVWR is 34320# with the ZF_IFS front axle. The tires that you replaced I assume were the XZA3 275/80R22.5 LRH not the newer XZA3 275/80R22.5+ Evertread tire. My XZA3's LRH came from mfr. original in 2007 which are the ones I'm replacing.

Larry.

[dickandlois]

Larry, The tires on my coach are smaller over all with a different axle. Your front axle weight is a good 5000 lbs greater them my setup.

What I wanted to let you know is that different series tires from the same supplier react differently to road conditions, loads and air pressure.

One needs to keep in mind the rim, dual spacing requirements and load range. The XZA3 series is a unique series and design.

Hope that Tireman chimes in with his extensive tire background.

Rich.

[tireman9]

Thanks Brett for the heads up. With 7 different forums on my list to monitor and two blogs to write I don't always catch every post that has a question.

I do accept direct email ( tireman9 at gmail )and a notice that there is a post and you would like a comment would be no problem at all. By using the post to ask questions we can hopefully help others who have similar questions.

Now to the question. I note that the understeer problem seem to occur in downhill travel. Do you notice any problems on uphill or flat road steady speed travel?

I note mandalay40F has a Tahoe toad. Any idea on its total towed weight?

**** & Lois do you have a toad? If so what is it? Weight?

My response will be shaped by this information.

RE inflation. Glad to hear you have had the coach weighed to learn the "minimum" cold inflation. However I see no problem with running plus 10% as long as you are not going above the tire max as molded on the sidewall.

Will check back this weekend to see what info you can provide.

[mandalay40f]

Tireman9,

I have the understeer problem with down hill turns that are more in the 45 to 90 degree range with posted speed caution sign +/- 40mph. Flat travel and up hill doesn't cause any issues. It is usually followed by entering the curve while decelerating to posted speed so I'm thinking the tail swing with the toad pushing could cause the rear tires to roll which is when the understeer starts. If speed is stable during the following horse shoe turns it performs much better.

I have had the coach 4 corners weighed twice and traveling loads in the seven years are consistent. Front axel is 12,600# and Rear is
20,500# GVWR 33,100# Allowable is 34,320# Toad is 5,200# GCWR is 39,520# Allowed is 44,320#. I have had alignment checks and are good as well as ride height and have Koni Shocks front and rear.

I set my tire psi per load and temperature Michelin charts @ as close to a 70 degree day for base setting and added 5 psi to F & R to
F0-110psi & R-100 psi which has helped. The XZA3 275/80R22.5 LRH tires I'm replacing for age are discontinued and the replacement tires are XZA3 275/80R22.5+ Evertread.

Short story I was wondering if the new Evertreads had any modifications over the LRH version that might help?

Also interested in any pros and cons of using the XZE's for more stability and what was ride like.

I'm happy with the existing tires as it rides like magic carpet with no vibrations or wobble but side walls started showing cracks.

Mandy40f

Larry

[rga48]

When I was replacing my tires, I was told by the shop that 90% of the tires they put on coaches are XZE's. I am currently on 49 day caravan in Alaska with many twisting and turning roads and I'm still very pleased with how well these tires have performed in comparison to the XZA3's. Because of my past experience with the XZA3's, I'm still gun-shy of right-hand turns but as I get more confident my cornering has improved.

[mandalay40f]

Thanks for the update information. I know that I'll never wear either tire out before they time out so that is not a factor in my choice. I feel that the XZA3's are targeted for high way long drive wear and comfort and not twisty two lane and rougher road conditions, i.e. the back roads of America and Canada. The specs. from Michelin kind of indicate this the difference in design.

[chp007kd40]

Mandalay 40f I think you have this figured out correctly. I have the same chassis under my Itasca 40 DP with Z-1, 8.9 and about the same weight. I just switched from XZE to XZA3 all steer tires and I like the smoother ride. I do live in Northern Ca. and I'm in the mountains all the time. The difference is, I don't tow anymore and It sounds like that could be the difference between the two types of tires. David

[tireman9]

Larry, Thanks for the additional info.

While I don't think it is tire roll it is understeer that goes to oversteer (vehicle turnes more than you want) probably due to the toad pushing the rear of the RV to turn more after you are into the turn. The hint to this is the fact that is happend when going down hill when the toad may not be slowing down as fast as the coach. When I was racing I was pulling a 26' enclosed trailer with a Camaro and all our tools and support equipment. My tow vehicle was a 1-Ton dually w/slide in camper. I had electric brakes on the trailer with controller under the dash so I could gently apply the trailer brakes when there was a downhill sharp turn. This would immediately get things under control and the trailer was no longer pushing the truck.

Now your toad is lighter than my trailer relative to the total loading but 5,200# is still going to push a little and when the coach in long and at an angle it is easier for a lighter load to generate a larger leverage force.

Now how do we fix this?
Your tire sidewalls at 100+psi are pretty stiff so I don't think changing tires is going to make much difference but increasing the coach tire pressure will decrease the tendency. I won't get all technical with cornering coefficients etc but increased coach tire pressure gives the coach tires more control in cornering.

A lighter toad will generate less of this turning force in corners.

If you can apply the toad brakes lightly but not the coach brakes (as I could with my set-up) that will also improve things. Also slowing down more before you enter the turn will decrease the rear swing out.

I see you mention "70 degree day" but this does not apply to tire inflation and the load tables. Set your tires when they are not in the sun, are the same temperature as the surrounding air and haven't been driven on for at least two hours.

"Evertread" seems to be a marketing item aimed at long thread life which for most RV owners is not an issue.

RE Ride. I am not aware of anyone doing a controlled test to compare tire-A vs Tire-B. Also based on my experience in evaluating hundreds of passenger tires on many dozen different cars it is not unusual to find Tire -C on vehicle X is better than Tire-D but when we test the same tires on Vehicle Q many times Tire-D is better than Tire-C.

Simply relying on what you felt with an old worn set vs a new set of tires is not a valid engineering comparison. In my opinion this is about as helpful as trying to compare your wife's chocolate cake vs your mothers or grandmothers.

[mandalay40f]

Thanks Tireman9 for the reply.

Yes, over steer is the correct problem. I will consider increasing the psi until I decide on which tire to get. I mentioned the 70 degree temp setting as it is the common psi line for the 110 psi and 100 psi. I waited for a even 70 degrees and set the psi's so it is easy in a cooler morning or warmer day to know what the tire pressure reading should be do to current temp reading on the temp chart. I use a temp gun and pressure gauge for checking when not in the sun and temp is even. I use the Temp gun for walk around checks during stops checking for any over temp issues. As for toad braking I use a air brake proportional system to match the coach brake so I'm unable to induce any pre-braking, which sounds like a useful tool.

Larry

[mandalay40f]

Thanks for all the post help!

I just want to report my first trip with the new XZE's v.s. XZA's 6 year old 35K mile tires. Same mountainous road on a rainy/windy day wth same tahoe toad. The handling was a definite increase in stability in cornering down hill turns and ride smoothness was very comparable, maybe old v.s. new tires. The comparison in turns are using posted recommended mph signs. I will try the same route without the toad and to compare toad pushing affect in the turns. I felt straight freeway driving was steadier with less effect from road crown steering me.

Larry

[rileylene]

Hello,

I have a 2009(built Oct 09) 37.5 Tiffin Phaeton with Michelin ZXA3's on it. They are 4 - 5 yrs old and just starting to get very small sidewall cracking and I always keep them covered and never put any tire polish on them. I see in this post that maybe the XZE's may be better.

What is the best tire for our coach, we do get some wandering on the road but the tires run very smooth and our fuel economy is good (Well for a house rolling down the road LOL).

We run 95 lbs in the frt and 98 in the rear.

Thanks

[pennzo]

Hi!

 

I am looking for assistance with replacing tires on my 2000 Monaco Windsor 38PBS with a 1RF chassis (Roadmaster, I believe?) and the tires are old Michelin XZE2+ 275/70/22.5 all around...the date code is 3510 for all 6....dry-rotting and overdue for replacement.

 

I am a member of FMCA, but am not thrilled into spending more than $3000 on new tires, but this option is looking rather improbable.... 

 

I spoke to a rep from Monaco who suggested 295/80's should be put on the vehicle, as the 275/70's, original specs to the coach, were giving folks tire issues when the vehicle came out new...plus it seems NOBODY carries the 275/70R/22.5 spec, I am feeling I can select between the 2, perhaps a 275/80, 280/75 or a 295/75...ideas?

 

We won't be using it much and hate to spend good money on Michelins (love the, BTW) if the vehicle isn't going to see regular use in the short term...

 

Any suggestions on brand and size would be most appreciative!

 

Respectfully,

 

Eddie Gerlach

Tampa, Florida 

321-297-2301

pennywise.eddie@gmail.com

[wolfe10]

Eddie,

Welcome to the FMCA Forum.

Couple of points:

HUGE difference between 275/70 and 295/80 tires. 545 revolutions per mile for the 275/70. 503 revolutions per mile for the 295/80.  The 295/80 is also much taller (overall diameter of the 275/70 is 38.0" vs 295/80 of 41.3") and a little wider as well. No idea if they would cause interference with body or suspension components.  Would sure want some "first hand" experiences from others with your  same coach before making that leap.

Not sure what the "problem" is with the OE 275/70's. Looking at the Michelin XZA2 which comes in both sizes, the single max load for the 275/70 is 6940.

What are your actual wheel position/axle weights?

[pennzo]

wolfe10,

 

those are good questions...we purchased the RV from a private seller from SC in 12/2016, drove it home to Mount Dora, Florida and then onwards to San Antonio and I used it for 6 months as temporary lodging when going to school with USAA...now, we're living back home in Tampa and I am charged with driving the ol' gal back to Tampa and the quotes I have from Beasley Tire here in San Antonio are $3000 out the door for 6 of the Hankook AH-37 18 ply, (which I understand is a good tire) or roughly $510-520/tire for the:

1. Michelin XZE (275/80/22.5 - $522 + FET) or the
2. Michelin XZE2 (275/80/22.5 - $512 + FET)

I'm not sure what the problem was with the original equipment spec, either...I also had it aligned and new shocks put on at Josam Frame & Alignment in Orlando in December 2015, prior to its maiden voyage (for us, anyway!)....but that was over 2.5 years ago....

 

Thanks for your qucik reply, sir...I need to make a decision soon (today!) as I plan on picking up the RV from Evergreen RV in New Braunfels on Saturday, 3/2....just feeling a bit leery of even driving it down to SA to Beasley to get the tires changed...am considering having Beasley go up there with the new rubber and handle it there...thoughts?

Hancook_Quote_22819.pdf

[wolfe10]

I would call the guy you spoke with at Monaco and ask specifically:

What were the issues with the 275/70 series-- were they overloaded?

Verify he did mean 295/80, not 275/80R22.5.

Without knowing your actual coach weights, kind of hard to give sage advice, as insufficient carrying capacity for actual load is the #1 reason for changing tire size/load rating.

[pennzo]

wolfe10,

yes, I am sure of it...Jim was a Monaco rep for many years (actually works now at Source Engineering / 541-343-0293)...he actually started a 'campaign' that brought original owners for the older Monaco with those sized tires back in to get the beefier tire setup....something along the lines of issues with load rating, blow-outs, etc...as far as the larger tire, his concern was ensuring that the bolts that secure the control arm on the rear axle face inwards towards the RV and not OUTWARDS, as clearance could be compromised...told me if I was working with a reputable shop, that shouldn't be an issue...

But must admit I'm a bit apprehensive stepping up to such a larger tire as I too am concerned about clearances.....being an O/O years ago, running exclusively Michelins (ZXA3+ for steers and XDA5's for drives, running 105 PSI with Centramatics on the steers and Cat-Eye's for inflation indicators for the drives on my KW's and Freightliners), I feel the existing tire size is more than adequate.  My feeling is the blow-outs possibly occurred with new owners not checking for proper tire pressures, overloading their RV, etc?

will follow-up and advise as to progress...thanks again! 

[wolfe10]

Jim Walls IS a good source of information on Monaco products and would likely be able to tell you exactly what the issues were with the OE tire size and if there would be fitment issues on your specific coach.

And you also need to verify your wheel size.  The 275/70 can be fit on 7.50 and 8.25" wheels.  the 295/80 on 8.25 or 9" wheels. You need to verify that you have the 8.25" wheels.  This will be stamped on the wheel and easily visible on the rear outers.

[wildebill308]

pennzo, welcome to the forum. I found this app handy in comparing tire size. https://tiresize.com/comparison/

Bill

[jleamont]

Eddie, I also have a Monaco product that had the 295/80R22.5 from the factory. When we picked it up it had the 295/75R22.5 on it which wasn't adequate to handle the weight of the coach. After research I went with the 12R22.5. 

In our situation the 12R was a little overkill for the weight (not a bad thing), it was a tire that is easily sourced should I need one, it fit our factory wheels, had no clearance issues under the coach and it was lighter than the other option (315/80R22.5) which helps reduce rotational mass for MPG's. Being such a common size pricing was fantastic. Sounds like you have some research to do.

Here is the link from the previous discussion;

 

[pennzo]

6 minutes ago, wolfe10 said:

Jim Walls IS a good source of information on Monaco products and would likely be able to tell you exactly what the issues were with the OE tire size and if there would be fitment issues on your specific coach.

And you also need to verify your wheel size.  The 275/70 can be fit on 7.50 and 8.25" wheels.  the 295/80 on 8.25 or 9" wheels. You need to verify that you have the 8.25" wheels.  This will be stamped on the wheel and easily visible on the rear outers.

well, that is also a good point...I have the Alcoa Accurides on there now....will ask Evergreen if they could verify rim size for me....thanks.....will continue with the research...whew!

[pennzo]

5 minutes ago, WILDEBILL308 said:

pennzo, welcome to the forum. I found this app handy in comparing tire size. https://tiresize.com/comparison/

Bill

thank you for the resource, Bill...sitting here in San Antonio and needing to make a decision soon as to size and type of tire today.....was planning on leaving back to Tampa this weekend, but may wait until Monday if I can't get this sorted today...cheers!  

[pennzo]

11 minutes ago, pennzo said:

thank you for the resource, Bill...sitting here in San Antonio and needing to make a decision soon as to size and type of tire today.....was planning on leaving back to Tampa this weekend, but may wait until Monday if I can't get this sorted today...cheers!  

wow...that is rather eye-opening, going from the 275/70/R22.5 that are on it now to the 295/80/R22.5 that Jim has proposed...am awaiting word from Evergreen as to the rim size on the Alcoa before proceeding....