Ram suspension problem

[richclover]

2018 Ram 2500 Tradesman, Cummins. Towed the camper to Mesquite, NV, and noticed a persistent steering pull to the right. I blamed it on the slope of I-15 and, maybe, the crosswind working on the camper.

But, driving home without the camper the same thing happened.

Off to the local Big O tire shop. Alignment was very close to correct and after adjustment, the truck still pulled right. Wheels rotated front to back, then left front to right front... No change. Brakes checked, no dragging brake.

But wait... I noticed the truck looked to be not level sitting in the garage. The right front wheel well measured about 2” lower than the left. Right rear is about 1 1/2” lower than the left.

Measurements confirmed by the local dealer today. No reason found yet. Confirmed no broken springs, coil all around. Shocks are okay. Ball joints okay.

10,000 miles on the truck...

Has anyone heard of a similar problem?

[richclover]

Grit dog wrote:
That thing should drive like its on a railroad track right now with that much caster and that much toe.
Caster being relatively equal does not explain the "sag" though. I now think it may be something else based on the caster numbers.

From the Thuren notes:

“...Always loosen the upper radius arm bolt before making your cam adjustments. If you do play with some cross-caster on a radius arm truck, do so at your own risk, and watch the chassis lean...”

That’s what caused the lean. Done by the first tire shop and not corrected by the dealer.

The lean has been corrected, steering wheel misalignment fixed and the truck seems to drive nicely. But it was a short drive home from the 3rd tire shop, which has won my future business.

Thanks again for the great info!

[Grit_dog]

That thing should drive like its on a railroad track right now with that much caster and that much toe.
Caster being relatively equal does not explain the "sag" though. I now think it may be something else based on the caster numbers.

[FishOnOne]

Man.... hope you get this one fixed. That’s got to be annoying

[NJRVer]

Should have added in my post the Thuren alignment was done at an independent shop.
Dealer would only align to what Ram says the alignment should be, which of course is no good.

[richclover]

NJRVer wrote:
My 3500 was pulling the same way.
Once I had the alignment done to thuren specs, no more pull.

Thanks! We're workin' on it.

The local dealer re-checked the alignment, made yet more corrections, couldn't find anything else wrong and suggested, this morning, that I take the truck to a body shop to look for a bent frame. IOW, the dealer was no help, didn't fix anything. In fact, after their attempt at alignment the pull to the right and right lean are still there. AND, the steering wheel is now off center. I don't have a dealer invoice yet because the service advisor I was working with is "off" today. I will, no doubt, be charged for yet another alignment.

So... The truck is now at the local Plains Tire shop. They, I found out, are very knowledgeable WRT Ram alignment problems since their alignment guy worked at the local Dodge dealer for years. They were very receptive to my explanation of the problem and possible solutions.

Fingers crossed...

[NJRVer]

My 3500 was pulling the same way.
Once I had the alignment done to thuren specs, no more pull.

[richclover]

Grit dog wrote:
^ What ScottG said.
Do some research on this and verify for yourself on the truck, but likely the caster adjustment on the front control arms is way out of whack.
Make sure the caster adjustment marks are the same or very close to the same and you should have 4+ degrees of total positive caster and very close to zero toe in for the best alignment.


https://www.thurenfabrication.com/tech/alignment-and-handling.html

That was an interesting read, thanks!

Especially note 4... Caster mis-adjustment causing lean. In fact, I don't recall seeing the lean until after the tire shop did the alignment.

I took the Thuren spec sheet and the tire shop alignment report to the dealer this afternoon. I've asked the dealer to realign the truck to Thuren specs. They'll cut off the welded jam nuts (recall drag link fix), and hopefully do it right.

The tire shop admitted difficulty getting good readings with the nuts welded...

Attached are before and after tire shop reports. Yes, the caster cams are set way different. Note the toe...

Before:



After:

[Grit_dog]

^ What ScottG said.
Do some research on this and verify for yourself on the truck, but likely the caster adjustment on the front control arms is way out of whack.
Make sure the caster adjustment marks are the same or very close to the same and you should have 4+ degrees of total positive caster and very close to zero toe in for the best alignment.


https://www.thurenfabrication.com/tech/alignment-and-handling.html

[richclover]

Tyler0215 wrote:
Sounds like weak springs. Get them all replaced not just the low side.
Still in warranty? You will have to fight to get them to cover all four springs

The local dealer, where I bought the truck new August 2018, got it in the shop yesterday noon. They "think" the springs are ok but I'll go by there later this morning and make sure they measure them.

The drag link recall (jam nut weld), was done by the same dealer in April this year. Alignment has been checked twice since.

No wrecks or overloading or frame twisting...

This "issue" is fairly recent. Cause unknown, so far. Right, the warranty is in play 😉

[carringb]

Busdriver wrote:
Frame Bent, had a friend with a new Ram frame bent

This is what I would suspect too. But aren't all the crossmembers welded?

I had an F650 rollback that got tweaked. Almost the same way, where the driver front corner was sitting about 2" low. Put new springs on. Twice. No change. Finally corner-weighed it to rule out springs, then center-jacked the front end. The frame was twisted about 5". Probably from loading a heavy truck while diagonal in a ditch. The F650s use Huck-bolts on all the crossmembers, so we loosened them all (got some good snaps and pops in the process), set it on jack stands, and torqued them back up. All was good after that.

[bucky]

You need to measure the frame, not the body.

[ScottG]

Recently read about a RAM that was doing the same thing. Turned out the allignment shop, in an effort to stop the live axle suspension from pulling away from the crown in the road, had turned the caster adjusters on either side completley different directions which is a total no-no.

[Busdriver]

Frame Bent, had a friend with a new Ram frame bent

[Tyler0215]

Sounds like weak springs. Get them all replaced not just the low side.
Still in warranty? You will have to fight to get them to cover all four springs