Strange Ram 2500 Vibration

[kfp673]

Hello All..

Sorry in advance for the long post, but I am looking to see if we have anyone else with similar experience or thoughts. I have a 2018 Ram2500 with the 6.4L 4:10. I love the truck and it tows my 35' TT very well. We just got back today from a 2k mile round trip with the trailer from PA to FL. In general it towed great and was a great ride but I experienced a strange vibration that sometimes lasted for hours and other times was gone..
Little back story, most of my camping is within 3 hours from me here in PA. To get to these parks I only use small stretches of highway and generally those roads are not in great shape so its easy not to notice things or blame the bad roads. I mention this because it is rare I get long stretches of flat interstate while towing my trailer.

So, getting right to it, when under load I get a pretty heavy vibration but only when traveling between 65-75 mph and only when torque is being used. The vibration is one that my kids thought was funny because they could say ahhhhhhhhhhhhhh and it sounded like you were beating on your chest fast. Quite annoying to me but at least they found it funny... :M

A few thoughts. It seems to me like something in the torque converter or somewhere else in the drive line. I say this becuase when the TC engages is the only time I feel it. For example, if I am cruising at 70mph, the vibration might remain there the entire time and at first I thought tire balance issue (even though I had them balanced last week and they feel perfect without towing) however the second I let my foot off the gas the vibration is gone immediately. Also, stomp on the gas causing the truck to down shift and for the first few seconds after the sift, no vibration. As the RPM's drop slightly as the TC engages the vibration comes right back. So I dont believe it is a wheel or tire issue as I would think that would present itself regardless of throttle.

Now for the biggest kicker... We just got back from a 2000 mile round trip. The entire 1000 mile trip heading to FL I mentally told myself it had something to do with the road condition similar to porposing because I would hit a nice smooth patch and BAM, it's gone. BUT, that proved to not be true and as the trip went on it proved to not matter. Obviously bad roads, or uneven roads cause bouncing or even vibration, but even on nice smooth roads I would get this effect a lot of the time and randomly it would disappear. 81N in VA I had a super smooth section where I could not lose the vibration for 2 hours. Stopped for gas and got back on the road and it was gone (or much less noticeable) for a while.

Now I know taking the truck to the dealer with this info is useless. Especially becuase I would have to bring my camper along and we dont have anywhere near me I can get them up to 70mph, so I want to do as much research as possible before engaging the dealer.

Am I missing something? Anyone ever have this issue? Thanks for your help!

[markandkim]

My 2016 Ram 2500 has the same issue @ 70 MPH, unloaded.

[parker_rowe]

It sure sounds like the torque convertor lockup from what you describe. Although it could just be another problem (like u joints) that gets magnified when the converter is locked.

If you maintain the same throttle setting when the vibration starts, and just lightly press the brakes enough to light the taillights, it should unlock the converter. Maybe that will help you narrow it down.

But obviously diag is hard to do over the internet.

[dapperdan]

A couple of guys already said it...... U joints!

My rear U joint started to “let go” with less than 50k on it on my old ‘06 RAM. Similar scenario, felt the vibration more when towing but it was still evident without pulling the trailer. Blocked the rear end up off the ground and crawled under it..... That’s when I discovered the bad U joint! I’m REALLY glad I caught it when I did as we wouldn’t have gotten too much further with that worn out joint! Doesn’t cost anything to look at your U joints, it’s a good place to start anyway.

Good luck!

Dan

[kfp673]

So I wanted to come back to this to see if anyone has more info. After paying closer attention, the truck does have this vibration type feeling even without towing, it is just MUCH lighter and harder to notice. If you were on a bumpy road you might think that was the cause. As stated above, it is always as I go over 65mph and approach 70, and I have to be on the gas. For example, if I am going 72 and it is shaking and I let off the gas the shaking stops immediately. Anything I as a non-mechanic can check before I try the dealer again? I am certain they will say no problem found. Drive shaft? TQ converter? As stated, unloaded it is very tolerable, but if I am driving solo I can watch the passenger seat start shaking as I get over 60 and approach 70. Thoughts?

[FishOnOne]

You may want to research Centramatic Balancing Rings.

[kfp673]

Thanks all. Sounds like not much I can do about it. Very annoying to say the least. I will keep working on it but I have no doubt taking it to the dealer right now will be a waste of time, so I will try some of the above suggestions. Thanks

[IdaD]

SidecarFlip wrote:
My only comment is... If you are towing at 75 per on any road, limited access or not, you have a deathwish. It's vacation, not the Indy 500. Slow down and smell the roses, especially with kids in the truck.

Meh, come out west someday. Rural freeways are generally lightly traveled with 80 mph speed limits with most vehicles going 85. I think a big speed differential can be more dangerous than towing at 75. There are also lots of 2 lane highways with almost no traffic on them with 70 mph speed limits. Go a few hours on one of those in wide open desert country seeing just a few other vehicles and 70 starts to feel like you could get out and run alongside.

[Krusty]

With your trailer connected, measure the distance from the rear of the truck to the ground. Disconnect the trailer, and, if you are able, load enough weight to the rear of the truck to lower it the same amount the tongue weight would. Drive it to see if you can duplicate the vibration without the trailer attached. It may be caused by driveline angles due to sag from the trailer.

[SidecarFlip]

My only comment is... If you are towing at 75 per on any road, limited access or not, you have a deathwish. It's vacation, not the Indy 500. Slow down and smell the roses, especially with kids in the truck.

[Me_Again]

Common issue with many of the new RAMs. Have the tires balance on a machine that does it lug centric, that is they bolt an adapter onto the wheel to balance. Problem seems to be with hub centric balancing and these wheels currently in use. Note: Your RAM is lug centric.

Some recommend Road Force Balancing. https://www.discounttire.com/learn/road-force-balancing?cid=cd9cc2eb-57a8-4425-859e-d9697a0def4e&gclid=CjwKCAjwzPXlBRAjEiwAj_XTEXvaS1UNIyJWpYP2vdsnj_dW9BAWF5wfJmkmEf9JW5CN7C-hsKpJqBoCYVsQAvD_BwE

Also some recommend Centramatic balancers.
http://www.centramatic.com/wheel-balance.rhtml?type=Light-Duty

Your RAM dealer will struggle with this issue! Many have had dealers throw lots of parts at this issue without solving it. The Frames of the new RAMs are very rigid, which seems to add to the problem. The 2020 RAMs are coming with frame mounted anti vibration devices.

Join a site like the Turbo Diesel Register.

Chris

[Lynnmor]

BenK wrote:
U joints

Best, cheapest and easiest place to start.

[BenK]

U joints

[iznab]

I have noticed the same thing with my 2014 6.4. I believe it’s the fan clutch.

[RobWNY]

If you Google Ram Truck Vibrations you'll see a lot of complaints about driveline vibration at highway speeds. You might want to read those before going to a dealer. Several people complaining about the same thing. Maybe there's explanations so you can advise your dealer what to check.