Tire pressure or just heavy?

[lexadmn]

A few months ago, we came across a 25' 94 Warrior on a Chevy P30 chassis (454 TBI, 4L80E, 4.10/14-bolt). The owner (a nice enough guy) quickly captured our attention by illustrating how well everything inside worked. He even took us for a ride in town. I asked about taking it for a drive myself and he was not open to this as he had no tags or insurance (I kinda get that).
After some thought, a pocket full of ignorance (and a little bit of cash) we bought in.
Shortly after, there were a few things that seemed to fail and we worked to correct as they would happen. One thing we did notice right away was how squirrely this thing on the road as though we were driving on a bunch of low tires.
If car or truck (no matter the size) were to pass, I would struggle to keep the MH on the road.
Driving on a curvy road was just scary.
We continued to correct to the tune of new exhaust, new tires, new steering suspension, new differential bearings, new wheels.
The old tires were some no name brand 7.50/R16's. Blow-outs seemed pretty regular the more we drove. No dry-rot, good tread, 10 pr.
I bought 7 Goodrich T/A's P235/85/R16 Commercial, 10 pr, load range E tires and 4 Eagle polished wheels (the steel wheels were just too ugly).
I also replaced both bell cranks, rotors, all bearings, new brakes and drag link. The rest of the steering "appears" to be tight.
The new tires recommended inflation up to 80 psi.
The new wheels recommend inflation up to 65 psi.
The tire shop put 65 psi in the tires.
Took it for its first drive and no difference. She is all over the road as if we had flats or low tires.
I realize this thing is a little heavy but compared to many others on here, she's just a runt (only a 25 footer).
Is this just the way it is for a MH? Should I get use to it? Or could something else be wrong?

[legomybago]

You need to go to a good front end alignment shop. Doesn't sound like you were at one i?? Did they even drive it? A good alignment person/shop can fix it.

Air bags front and rear make a huge difference....

[Rickf1985]

I agree on the alignment, not so much on the air bags. Bags on the front maybe but if they are needed on the rear you are too heavy. Let me ask this, Have you ever driven a motor home before? These do not handle like a pick up truck. They will blow around when a big truck passes. It should not be uncontrollable or excessive though. The alignment would be first and foremost since you have changed so much stuff in the steering. The wheels being rated at only 65 lbs. are not heavy enough, you need to have the RV weighed in a ready to go camping mode. Full of water, gas and full propane. See how much it weighs front a back axles and then consult BF Goodrichs tire load/pressure charts to see what pressure you should be running. I will bet it is over 65 lbs. If it does not already have one a large rear sway bar makes a huge difference. Also a rear track bar can help if the springs are not holding the side load. (Tail wagging the dog)

[EldoradoBill]

You have E-rated tires on D-rated rims; not good. You need 80 lb in the tires to handle halfway decent. I tossed 7 Cooper 215/85-16D tires for 235/85-16E Firestone Transforce and the difference was unbelieveable.

[lexadmn]

This is my first time driving a motorhome. I have many hours in 3500 series box trucks but none have walked like this. Again, it is like driving on several low tires or very heavy load. Not leaning, just the back end walking side to side in light turns and the front feeling soft.
I have not had the front-end aligned. I am finding it a challenge to find a place in the area that is able to do this. I'll keep looking.
The front and back are already bagged. I have around 45 psi in front and rear.
The tire shop asked for my manual to find Gross weight and that is why they recommended this tire.
They did not drive afterwards - just installed tires and wheels. They did have 80 psi in the tires on the aluminum wheels at first, but when the seen the 65 psi max, they let air out.
The wheels I ordered from Summit. They recommended I call Eagle because of the gross weight, and I did.  These were the wheels they recommended. None of the paperwork said anything about 65 psi but this is cast into the wheel under the center cap "65 psi max".
If the aluminums are part of the culprit, I do still have the steel wheels.

[Rickf1985]

Since the wheels were recommended obviously against DOT regulations you should demand your money back! I am quite sure they were very expensive. It sounds to me like you could use a rear track bar but you need to have it aligned first off and see what it does. I would not run it for long without weighing it to see if you are overloading the tires. You could ruin a new set of tires real fast running them underinflated. You should have it weighed before having the alignment done also. Any good truck shop will be able to align it.

The suspension in a motor home is much softer than in a delivery van. People do not want to be bouncing down the road in a motor home they paid 80 grand for. Hence it will ride softer and move more than a hard sprung delivery truck.

[lexadmn]

I have found a local shop that I am dropping it off at this evening for an alignment.
I will not be able to weigh it as I have no idea where to get this done here in Cornfield County, IL.
Not sure what to say about the wheels except disappointing.
Maybe this shop will have some answers when I pick it up tomorrow.

[BrianB]

I will not be able to weigh it as I have no idea where to get this done here in Cornfield County, IL.

Any truck stop along the highway with a CAT scale can weigh it. Other places include gravel pits or grain elevators that weigh trucks going in and out with materials.

[Rickf1985]

CAT scales are the best because they can weight the front and rear axle in one shot.

[EldoradoBill]

You wrote you bought 7 tires and 4 wheels-which positions have the steel wheels and which have the aluminum? I would think you would want the same all around......


Bill

[lexadmn]

The aluminum are on the front and on the outside rear.
I thought the same and was prepared to buy 6 wheels but when I called Eagle, their tech insisted that steel must be used on the inside rear and aluminum on the outside.

The front wheels are a different part number than the rear but I suspect this is because the outside if the front wheel is polished compared to the inside of the rear wheel.

[Rickf1985]

Kind of eliminates ever rotating tires doesn't it?

[EldoradoBill]

You need matching wheels on the duals. And from experience, I will say that 65 lb on the rear tires with that heavy rig is going to give you squirrelly handling. The whole deal with mismatched wheels sounds like a mess but hey, just this guys opinion.


Bill

[Rickf1985]

I don't understand the need for a steel wheel on the inside other than galvanic corrosion will make it a bear to get off. No different with the front. Now the inside of that wheel is going to be a mess after that, maybe that is the reason? My concern would be galvanic corrosion between the aluminum and steel wheels. Be sure to constantly check them for being tight.

[BrianB]

I think you'd be better off with the steel wheels at the correct pressures. Safety beats pretty any day.

You can dress up the steel wheel with a good coat of paint like I did, or you can get a set of chrome simulators for about $250.

Try to get your money back on the wheels since they gave you bad advice. If you can't, craigslist or ebay them to recoup some of your money.

[legomybago]

Running a steel wheel on the inside duel is just a cost saver. We used to do that in the trucking business. (aluminum wheels are spendy)They actually sell gaskets that slide over the studs to go in between the mating surface of the steel/aluminum wheels to keep contact to a minimum to help with corrosion. (I would put the steel wheels back on, and buy stainless wheel simulators), or buy "expensive" aluminum wheels to get your psi rating back up.

[tmsnyder]

also any scrap yard will have a truck scale.

[lexadmn]

Sorry for not getting back with the group sooner but here is what I have learned so far....

The front end has some wear and parts must be replaced before an alignment can be done.
Drag link/Center link is worn.
Outside Right tie-rod end is worn.
Parts, labor, alignment - $912.00

I support the shops, just couldn't afford that amount at this time.

I have replaced the drag link. I will probably go ahead and take it back to the shop and let them replace the tie-rod end and align. Installing the drag link cuts the cost around $500.

[BrianB]

All good and needs to be done. But.... that still doesn't solve the tire pressure issue you have and will continue to have after the front end is fixed up. I still maintain that you should get your money back on those wheels and have it be correct.

Returning the wheels would give you money for the front end fixes plus towards a set of chrome simulators. The stainless simulators are only about $145 for 16" GM rims. https://www.amazon.com/gp/product/B000CP2I2G

[shortbus]

Even on my smaller coach steering feels really loose and wonders around the road with anything less than 70psi in the front tires. I keep them up around 75psi and it drives much much better than anything lower.

[shortbus]

Oh, I have one of these too, probably helps a lot:


http://www.safe-t-plus.com/our-products/

[FrankenHome]

One thing I don't think I saw anyone mention is the gvwr. This should be on plate riveted on the drivers door (if you have one) or somewhere where you can see it. It may also have the recommended tire pressure.


I have 16 inch tires on my 96 Winnie and the GVWR is 15,200 pounds. The recommended tire pressure is 80 psi. Necessary to safely support the max weight.  With a full set of new Michelins it rode like a log wagon at 80 psi and was difficult to handle on the open road. My solution was a new set of shocks, rear sway bar bushings and Firestone Ride-Rites front and rear. The upgrades took care of all my handling issues. It holds a line very nicely now and I can keep it there using light corrections.


I would be seriously concerned running under inflated. This could cause an eventual tire failure (blow out) as the tire heats up expands then cools again and contracts repeatedly. This under inflated expansion and contraction fatigues the tire side wall resulting in tire separation. Following all the previous recommendations, I would do whatever I had to do to get the right wheels and inflate the tires to the correct pressure.


If someone has already covered this.....never mind!


John

[lexadmn]

Good point.

The GVWR is 11,800.

Axle and Tire Information:
FRONT-4300     7.50R16 @ 65psi Single
REAR- 7500      7.50R16 @ 65psi Dual

KC

[Rickf1985]

I find it interesting that you guys with the "newer" Winnies are running 16 inch tires. Especially Frankenhome with a 31 footer. I would think that they would have stayed with the 19.5's. Interesting.

[TerryH]

Mine is older and shorter and lighter, but also 16's that call for 65psi. I find that a little spongy, 70 works fine. Mind you I am a touch on the heavy side, especially with gas and propane tanks full.