Shudder on take off, towing

[jelag]

So I have a 13, 3500 2WD with the 68RFE transmission and when towing (15K lb trailer) I get a shudder on take off... So I started to put the transmission in 1st gear, thinking the transmission is starting in too high a gear... YEP Tow/Haul is engaged.... so I'm driving through a couple of small towns.. and I forget to put the transmission in 1, and I don't feel the problem.... than I'm pulling out of a parking lot making a turn and the shudder is back.... as I start to chase this down, I notice that the shudder is only there when the truck is making a turn...

So I'm wondering if I really have an issue with the posi-trac in the rear end and the clutches... and I'm assuming that all the newer trucks have a posi-trac rear end of some kind....

Maybe one of you guys has an idea.... I've read and commented about others with the shudder.... could it be someplace else besides the transmission?

Thanks... Jim

 

[lpennock]

Limited slip differentials is an option so the truck may or may not have one. The LSD used in these trucks are a Torson style so no clutches.

 

[Bob4x4]

The diff is set up to be a good traction aid.When heavily loaded on pavement it is more noticible.

 

[RustyJC]

Even though his truck (like mine) uses the 11.8" versus 11.5" AAM rear axle, I recall Cummins12V98 complaining of a shudder when turning while towing with his 2015 Ram 3500 at about 25,000 miles since new. It was cured by a fluid change in the rear axle.

Rusty

 

[ranger 393]

I know this may not be your problem, but mine developed a shudder on take off and would go away as speed increased. Long story short I had a rear brake caliper that was in a bind on the caliper pins , took it apart and cleaned and greased the pins ,and shudder gone.

 

[Cummins12V98]

I would say as Rusty mentioned the gear lube is TOAST! Do not exceed what the owners manual says for change intervals. IMHO the AMZ/OIL SevereGear 75-110 will go much longer than the OE fill.

 

[jelag]

Cummins12v98....

So the truck, new to me has 45K miles and at the time I bought it, it had 40K... The adapter to change hitch was still new in the plastic cover, and there was no evidence of wear in the hitch.... and there had not been a 5th wheel hitch installed... So until 1500 miles ago this truck has never towed.... this is my first tow with the truck....

Did you narrow the shudder down to when you started to pull on a turn, like I've seen, or did it also shudder on a straight pull as well...

Thanks... Jim

 

[Bob4x4]

If you don't have service records change the diff fluid and move forward.

 

[TCDiesel]

This take off shudders has plague Ram AAM for 14 Years. I myself have experience it at one time or another on every 3rd-4thgen Ram 2500/3500 I've own, had 100s of customers complain about it.. I have found this Shudder to be related to a number of things form GL to Sticky Rear brakes, pinion bearing failure, Axles, Joints , yokes, etc, it has driven me to the point of occasional Shudder is normal. predictable Shudder is a problem and needs addressing , During the hunt for this take drugs or alcohol for the heads aches and pain it will create. In other words in most cases occasional shudder is harmless go's away after a few turns AFTER pulling and HWY driving or straight driving. Just consider it a Butt cheek checker and carry on.

 

[Cummins12V98]

Cummins12v98....

So the truck, new to me has 45K miles and at the time I bought it, it had 40K... The adapter to change hitch was still new in the plastic cover, and there was no evidence of wear in the hitch.... and there had not been a 5th wheel hitch installed... So until 1500 miles ago this truck has never towed.... this is my first tow with the truck....

Did you narrow the shudder down to when you started to pull on a turn, like I've seen, or did it also shudder on a straight pull as well...

Thanks... Jim

Mine only had the shudder when turning from a stop. Changed out the GL and all has been well since. I had the GL tested by Blackstone and it was toast! I do admit I ran it too long but with over 50K on the AMZ/OIL GL it still was a nice golden brown on my 11 HO dually with at least 25K of that towing 28-29K.

Note the two viscosity levels.

#ad

 

[CUMMINZ]

About 18 months ago we changed GL and found slivers of steel in it. Ran it for 6 months and found more. RAM dealer took my PML cover off and we looked at spider gears and they were spauling off. Ordered pumpkin and had shop in Charlotte install it and also changed ring/pinion to 3.73. I can't remember how long ago I had a shudder. Best I can remember we added a can of the LS fluid and it stopped. I am 65 years old and don't think I will ever own another new truck. My 68rfe transmission has given me great service. It has only several times given me a shudder and that was when my mind was somewhere else and I did not paddle shift it and it shifted into 4th and TC locked in under load. We ordered a new SunCoast towing grade transmission yesterday. Just bought a new CC RV 41' long and 18k GVW coach we plan to tour the western US this summer and we were sure the 68 would be tested greatly. The SunCoast will give us great service if performs as advertised.

 

[dfb]

My 15 does it as well.. Really bad when pulling over the mountains near Weaverville. Road construction has us stopped on a steep grade. When we started pulling 13k lbs up YHE grade the entire truck shook... it happens towing from a dead stop. Depending how much pedal, it can get bad...just ignore it... Brand new it has done it..

 

[RustyJC]

Sounds to me like 2 different problems are finding their way onto this thread:

1. Shuddering when turning from a stop - differential action, possibly due to axle lube being depleted and overdue for a changeout.

2. Shuddering from takeoff in a straight line - pinion angle problem that's been around since Moby Dick was a minnow. If you adjust it so that it doesn't shudder when towing, it will shudder unloaded, and vice versa. All you can do is hope to find the best pinion angle adjustment compromise and not lay into the skinny pedal on the right until it's rolling to minimize axle wrap (which further exacerbates the pinion angle problem).

Rusty

 

[jelag]

Rusty... I thought it was all the time... than when in a small town, I was at 5 or 6 stop lights and no shudder.. as I watched it closer... I noticed it was just turning... I've put another 1000 miles, and I'm now sure its only when turning in my case... as soon as I get home I'm going to change the GL... but that's another 7-10 days on the road...

 

[CUMMINZ]

About 18 months ago we changed GL and found slivers of steel in it. Ran it for 6 months and found more. RAM dealer took my PML cover off and we looked at spider gears and they were spauling off. Ordered pumpkin and had shop in Charlotte install it and also changed ring/pinion to 3.73. I can't remember how long ago I had a shudder. Best I can remember we added a can of the LS fluid and it stopped. I am 65 years old and don't think I will ever own another new truck. My 68rfe transmission has given me great service. It has only several times given me a shudder and that was when my mind was somewhere else and I did not paddle shift it and it shifted into 4th and TC locked in under load. We ordered a new SunCoast towing grade transmission yesterday. Just bought a new CC RV 41' long and 18k GVW coach we plan to tour the western US this summer and we were sure the 68 would be tested greatly. The SunCoast will give us great service if performs as advertised.

Have now put 6,100 miles on the new Suncoast towing transmission with gross of 27k+. Have no shutters at all. When I get home I will for sure go back to 4.10s. also will not purchase another new RAM till they replace the 69aisin.

 

[jelag]

UPDATE - So I finally got around to changing the Differential Oil.... I installed the 75W - 110 Ams-Oil Sever Duty, full synthetic oil... I was sure that I noticed a change immediately but wanted to get a chance to tow...

The past few days I had the chance to tow my 15K lb 5er several hundred miles.... Absolutely no shudder....