Rear Tire recommendation 85 PSI?

[CapnDean]

I just had 8 new tires installed on my new to me Monaco Camelot 42PDQ.  I was expecting to see 100-110# in the 6 rear tires.   The label in the coach recommends 85?   Max tire pressure on these (GoodYear G70 295/80R22.5) is 120#.    I like to be close to max inflation,  85 seems too low.  Anybody got any logic to share?

 

[Ivan K]

You have to know your weight per axle or better yet per wheel and cross reference it to manifacturers recommendations.

I for instance have 95psi in drive wheels and 75 in tag. So it all depends...

[Pduggs]

Ivan is right. You have to get the coach weighed and preferably get weights at each axle end. You then take the higher weight from each axle end and go to the tire chart from your tire manufacture to determine psi. I did this at the Escapees park in Florida after I had purchased my coach and had placed everything in the coach. My pressures are 115 fronts, 95 drives and 85 tag. Coach rides well. 
I suspect if you were to air all your tires to 100-110 your coach would not ride very nicely and you might be too low in front. 
I had service done at Cummins a couple years back and they wrongly air all my tires to max pressure. As soon as I got in the coach and drove a short distance I immediately knew what they did. The coach rode like a tank. 

[Joel & Susanna]

Interesting comments indeed. I recently purchased new tires from a Goodyear Truck Center and they inflated all to 115 psi. I then took my Safari across the street to a truck front end alignment garage and they suggest running the steer tires at 125 psi which is max on the tires. I noted a much harder ride and subsequently adjusted these back down to 115 and the coach got smoother again. Not so sure about the front end alignment suggestion and frankly, these new tires will get outdated way before I wear them out.

[ktloah]

Agree totally with Ivan and Pdugg's comments. After weighing my 04 Dynasty, I run 115 front, 95 drives, and 85 tag....rides well, handles well too.

[W7BE_Bob]

Inflated to max when it's not needed means greater wear in the tire center and less  road contact. Tire mfgs recommending setting PSI to their inflation tables based on weight. 

My Toyo's are set to 115 with 14,700 lb, 90 with 19,600 lb, 80 with 5,000 lb steer to tag per weight. Weight is fully loaded includeing fuel, water, propane, passengers. 

Even the 14 lb cat was included. 😼

If the above weights look strange it's due to poor Monaco design. Increasing the tag to reduce the drive with it's 20,000 lb max, overloads the steer. There is no practical solution to moving cargo to the rear. But we try hard storing cases of wine in the back. 😀

 

[Ivylog]

04 Dynasty...85 drive and 75 tag based on axle weighs. Put 6 11R 22.5 on the rear at 10 years and had to increase pressures to 95 and 80. The rear doesn’t need the load carrying of a 295.

[dl_racing427]

Weird that the newer coaches seem to bias more weight toward the front.
On my 1993 Dynasty I have higher weight per tire on the drive than the steer.
I don't recall the exact weights when I weighed it, but I put labels above each tire to remind me of correct pressure.
IIRC I run 105 in the steer and 115 in the drive tires. 

Of course, I'm towing with a weight distributing hitch to avoid overloading my drive axle, but even without the trailer my tire loads are higher in the rear.
I feel much safer with the steer tires being well below their limits, as a steer blowout is much more dangerous than a drive.

[Guest Ray Davis]

1 hour ago, dl_racing427 said:

Weird that the newer coaches seem to bias more weight toward the front.
On my 1993 Dynasty I have higher weight per tire on the drive than the steer.

 We all know that coaches got heavier over the years to the point that many were over loaded on the rear axel .   

 When a tag is added it carries some of that overload in the rear but also shifts some of it to the front , it's not as simple as it first   appears .

 I recall reading on here that previously some toll roads were denying access to overloaded motorhomes until an exception was made   for RVs .  We are lucky   that the law seems to take a lenient attitude toward our coaches , lets keep it that way .  Maybe they feel that   could be my mom & dad or hopefully me   someday .

 

Edited November 13, 2020 by Ray Davis

[Ivylog]

In 2012 a highway bill made 24,000 lbs legal on a single axle for MHs and Buses. Around 2003 Monaco DOs got so bloated (longer, multiple slides, tile, extra) that they had very little CCC. The solution was adding a 10K tag axle.
Fortunately Monaco used some 23K drive axles in 2004-09... my 08 Navigator has a 23K drive which it needs even with a tag.

Around 2005-6, Monaco moved the fuel tank further back (not right behind the front axle) to lesson the weight on the front axle.

[jwms221@att.net]

I have the same coach that you do. Also had it weighed on two different occasions. I doubt that your loaded weight will differ much from mine. Have always ended up at 112-115 on fronts, 85 on drive, and 80 tags. Good tire wear and good ride. Good luck with your unit.

John W

2009 Camelot