Tire pressure

[letsgorving]

What tire pressure is everyone running on DX3

[retired18whler]

If its a Michelin 275 80R 22.5 the psi is 110 always. If you are empty is 110, if you are full it's 110psi.

[letsgorving]

It was delivered 90 all tires.

[A32Deuce]

That is more then likely what the factory puts in when they build the chassis.

[sconnors11]

I might be able to help here...

Best way is to weigh the front and rear axles and use the following link:
Michelin RV Tires | View Michelin RV Tires load and inflation tables for motorhomes and recreational vehicles. | Michelin RV Tires

Use the same pressures for all tires on the same axle.

If one side is more loaded than the other, use the heavier weight for the axle. For example, if one side is 6000 lbs and the other is 7500 lbs, use 15,000 lbs for the axle. Divide by the number of tires and inflate accordingly.

The table for the tires on my Force HD is attached.

I haven't weighed my coach yet, so all my tires are at 100 psig. I'll weigh them before our first trip, next weekend.

In general, nothing terrible will happen if you keep them at max pressure. Lowering pressure may smooth out the ride and increase the contact patch with the pavement.

Hope this helps,
Sean

[FOURWHL]

That^

Make a stop at a truck stop and weigh your rig loaded up. I suppose you can run max pressure as mentioned, but its going to affect ride quality. What you want to do is ratio your percentage of total axle capacity accordingly with the capacity of the tires. Once you do this for a "full load" you shouldnt have to do it again unless your setup changes.

Anecdotally, Here's my ticket and setup. With this I run 95 in the front and 100 in the rear. Tires are Max 110 likely same as yours.

[mookieblaylock]

Was your rig full of fuel, fresh water, passengers, gear, etc when weighed? That's a good bit less than I would have expected (which is great).

[FOURWHL]

Yep had just fueled, had a load of fresh. Black/grey were a bit empty as we were only a day into the trip. But full of food, gear, spare parts, etc.

But you're right. I was pleasantly surprised at how much room there still was.

Rear axle is rated at 21k so that seems to be what's going to be the limiting factor to watch. I've added a gang box to the nose of the trailer so I should really get weighed again one of these days, but I try to offset that with positioning the jeep.

[retired18whler]

Our DX3 has "truck" tires on it. You can play around with tire pressures all you want, an I do know that under inflation truck tire is going to heat up going down the road risking failure.
Running mine at what they are supposed to be doesn't really effect our unit smoothness.
.. poor roads to blame for majority of ride.
Trucking Companies never alter psi for any given load. I'm just trying to give a bit of insight to truck tires which are very different than auto tires etc
Safety is my greatest concern for everyone which is the same for all Motor Carriers companies.

[retired18whler]

I stand corrected after checking- always run 110 psi in steer tires, you can very the rears by 100psi to 110psi tire dept says... motor carrier companies also take into account how many ply the tire is behind cab are also to determine its needed constant psi.
So, how many ply your tires are may be an interesting new subject for you to decipher and determine new conversations with.

[bclemens]

FYI, we had a guy running max air pressure and had a crappy ride. Was looking to trade, get something fixed, etc, etc. Put the rear tires at the proper pressure and that solved all the issues.

[Webefine]

Originally Posted by retired18whler

If its a Michelin 275 80R 22.5 the psi is 110 always. If you are empty is 110, if you are full it's 110psi.

I disagree there is a reason that every major manufacturer of truck tires have load charts available. Matching your air pressure with the load that you are carrying will give the best ride quality and tire life.

[Tireman9]

I suggest you first review THIS post and after assembling the needed information re-submit your question if you want something better than a guess.

[sconnors11]

Just another data point, choose what is right for your own rig:

I had my 37BH weighed, consulted the load inflation chart, and now run my tires at 85 rear, 80 front. The ride has improved quite a bit. The truck seems to wander a bit less than when I had both axles at 95 psi.

I also installed the crossfire system in the rear axle to minimize undue stress on the inside tire from road crown and brake heat.

[Tireman9]

Originally Posted by sconnors11

Just another data point, choose what is right for your own rig:

I had my 37BH weighed, consulted the load inflation chart, and now run my tires at 85 rear, 80 front. The ride has improved quite a bit. The truck seems to wander a bit less than when I had both axles at 95 psi.

I also installed the crossfire system in the rear axle to minimize undue stress on the inside tire from road crown and brake heat.

If you are running Crossfire then you really need to get a TPMS system so you would be warned of an air leak. While the crossfire is suppose to only allow 10 psi or so to transfer the result of the transfer is the non-damages tire is now lower in pressure and could be overloaded ifenwithout the leaking tire ultimately transfering 100% of its load to the "good" tire. This overload can do structural damage to the "good" tire.