Violent side to side rear end shake

[Jlselectric]

I have a 2018 Ram 3500 dually long bed. It currently has 1250 miles. When I changed lanes the other day the truck hit a small bump in road and the back of truck started shaking and the shaking continued to get worse until I came to a complete stop. Then it did it again yesterday on a small curve that had a rough spot on the road. Both times my speed was under 40 miles an hour. The shaking is so violent that the truck literally feels like it is going to come apart. It will only stop when you come to complete stop. I took to dealer and was told the shaking was normal until you put more weight in truck. They put truck on rack and said all looked normal. This is not normal unweighted bounce. This is a side to side shake that increases exponitially until
Truck is stopped. Has anyone else had this happen?

 

[Dieselnut59]

Sounds like the "death wobble" that some of the older trucks had on the front end. Never heard of it on the rear end though?

 

[JR]

What's the rear tires air pressure set at?

 

[AEdelheit]

Are you sure its coming from the back?? It does sound like DW, while the back may bounce around alot unloaded it should settle down without coming to a stop.

 

[Cummins12V98]

What's the rear tires air pressure set at?

If it's the rear i'm betting 80psi unloaded.

 

[6.7LRigby]

Are the lug nuts tight?

 

[Mark31]

A cracked steel rim, a separating tire, a bad shock, bad rear end bearing, bad carrier bearing. Ride a while then put a IR gun (or your hands, if you can't get one to use) on everything from the trans back. Try recreating an event in a lower gear. Rear end full of oil? If you don't find anything, I might consider changing the rear end oil to see what's in it. I would fear a loss of control failure and would stay out of traffic until fixed, unless I don't understand you correctly.

 

[Ozymandias]

Mark hes truck is brandnew, right from the dealers lot, shy 1000M old.
I do not think that he should do some DIY works.

 

[KATOOM]

Absolutely agree..... Dont do ANYTHING to your truck. Its brand new. Take it back to the dealer and talk to someone else or take it to a different dealer. No violent shaking is normal, loaded or unloaded. Cant freaking believe some of the crap we hear some dealers pawn off on customers...

 

[Mark31]

OZ and Katoom, I know the truck is B.A.N. (brand a$$ new), but that doesn't mean that it doesn't have a bad part. It will cost jlselectric just some of his time to investigate (not repair) if he so chooses. As far as changing the rear end oil, I should have said if he has any questionable heat IR temps, ask the dealer to consider changing it to see if anything shows up. My bad!! The main things is no one hurt.

 

[KATOOM]

OZ and Katoom, I know the truck is B.A.N. (brand a$$ new), but that doesn't mean that it doesn't have a bad part. It will cost jlselectric just some of his time to investigate (not repair) if he so chooses. As far as changing the rear end oil, I should have said if he has any questionable heat IR temps, ask the dealer to consider changing it to see if anything shows up. My bad!! The main things is no one hurt.

Its just important to stress the fact that if the owner does anything to their new (in warranty) vehicle then it can easily become a problem which may void their warranty. Why ever chance that??? Take it back as many times as you have to, as thats what you paid (probably close to $70,000) for...

 

[ram17]

Sounds like shocks, or loose bolts on suspensions components or undercarriage. Although it feels like it is coming from the rear the source of the problem could be in the front end. Go back to the dealer and insist that a diesel technician or the service advisor/manager ride in the truck while you recreate the problem.

 

[Too Tall]

Take it back to them, I believe after 3 attempts FCA will buy it back. They have a lot of liability if you have an accident. Make them fix it, Get FCA involved.

 

[AMink]

If it's the rear i'm betting 80psi unloaded.

Rears should be at 65 but even 80 shouldn't cause what is being described. I have the same truck with around the same mileage and have been tooling around empty on some pretty beat up roads. No ride issues at all. Sounds like something is loose.

 

[Cummins12V98]

Rears should be at 65 but even 80 shouldn't cause what is being described. I have the same truck with around the same mileage and have been tooling around empty on some pretty beat up roads. No ride issues at all. Sounds like something is loose.

Rears "SHOULD" be 65psi when hauling full rear axle rated load. Just bobtail and lighter loads 30-35psi is more than enough pressure.

 

[AMink]

Maybe his squeak is your shake.
https://www.turbodieselregister.com...one-up-is-an-idiot.264567/page-2#post-2556808

 

[Bob4x4]

Take it back to them, I believe after 3 attempts FCA will buy it back. They have a lot of liability if you have an accident. Make them fix it, Get FCA involved.

There must be an attempt to repair made for that to true. The issue has to be duplicated by the dealership then repair performed.
The best course of action is to test drive with appropriate dealer personnel reproducing the concern

 

[AMink]

Any word on the cause?