Vibration Highway Speed

[RSOUDER]

I live in Florida and I purchased a new Ram 2500 4x4 Laramie Crew Cab Diesel w G56 transmission out of town. The vibration starts around 65-70 mph and felt in the seat and floor. The Three local Dealerships say its the tires. After 19 tires from Firestone (Ram doesn't warranty tires) I drive 11 hours north to the Dealership I purchased it from. They replaced 2 axles, 2 hubs, 2 rotors, and all new wheels and tires. The ride improved but the vibration is still there at the same speed. The Dealership says it is the characteristic of that truck. They let me drive two new similar trucks on the lot and they both have the same issue. I'm surprised there is not much discussion on this topic. Long term consequences will bring fatigue and premature failure on drive line parts, let alone owner fatigue and frustration. My 05 Ram 3500 4x4 QC SRW SB Diesel with 300000 miles doesn't have this problem. Does anyone know of a solution?

 

[DHayden]

My 2015 was smooth as can be with the stock wheels/tires. I swapped them with the 19.5's off of my 2001.5 and I got a bad vibration starting at about 65mph. The 19.5's didnt have any vibration what so ever on the 2001.5 even at 85. Going up steep hills or even coasting down seems to exasperate the issue. I put centramatics on but the problem is still noticeable although much degraded.

 

[sag2]

My 2018 also has a fairly good vibration over 70 and really bad at 80. I put it up on the rack at school and ran it and it seemed to be coming from the rear. The rear tires also did not look round. We didn't have the right hub adapter so when I spun them up they were not running perfectly true and were showing 4 or 5 ounces off. I had the dealer balance the two rears and it didn't make much difference. I have not driven it in the last month or so and have not had the time to look deeper. Since I don't have a vibration analyzer any longer I can not rule out drive line, but it feels like tires to me. Luckily I don't run 75 or 80 much, but if I did it would be pretty annoying.

 

[RSOUDER]

My theory is Ram may have a bad batch of parts. The reason I say this is I put the truck on jack stands and ran it up to 70 mph (make sure to turn off traction control) and the left rear tire has some run out side to side and up and down. The right rear looked pretty good. I then took the rear tires off and ran it up to 70 mph. Both rotors had run out and the left rear caliper was rattling (I secured the rotors first). I pulled both rear rotors and did the same for the hubs. I saw movement in both hubs so I then check them both with a micrometer. The right rear was at 0.015" and left rear was 0.020" on the hub face. That's way above factory specification of 0.005". I will dig into it some more and check the new parts. Hopefully there is a fix.

 

[TCDiesel]

My 2018 also has a fairly good vibration over 70 and really bad at 80. I put it up on the rack at school and ran it and it seemed to be coming from the rear. The rear tires also did not look round. We didn't have the right hub adapter so when I spun them up they were not running perfectly true and were showing 4 or 5 ounces off. I had the dealer balance the two rears and it didn't make much difference. I have not driven it in the last month or so and have not had the time to look deeper. Since I don't have a vibration analyzer any longer I can not rule out drive line, but it feels like tires to me. Luckily I don't run 75 or 80 much, but if I did it would be pretty annoying.

I have the same problem Saga2, I've done everything you name except for 1 Piece DL, its good until 70- 75 then gets worst real fast.

Its somewhat contributed to tires I had Toyo CTS and it was horrible, swap to Toyo ATs better, Now have Michelin defenders. I have Centramatics and Balance Masters, I have done every type of balancing known to man.

I also swap tires form My 14 to 13 and 13 to 14 same problem on the 13 , Although the Toyo CTSs just suck at hwy speeds above 65 MPH.

 

[Dieselnerd]

My '05 SRW 3500 had the same problem. I put in a one piece driveshaft and that fixed it.

My '14 DRW has been very smooth even up to 85 mph which is as fast as I've ever had it.

 

[RSOUDER]

My '05 SRW 3500 had the same problem. I put in a one piece driveshaft and that fixed it.

My '14 DRW has been very smooth even up to 85 mph which is as fast as I've ever had it.

Thank you for the reply. I wish I could say the same. I have a one piece shaft from the transfer case to the rear differential. We put a vibration analyzer in different locations on the truck. The left rear makes the most vibration. It comes out at 12 HZ at 1800 rpm which translates to a bump every revolution of the tire. That could be tires, wheels, rotors, hubs, axles, bearings, ring and pinion. Dealer replaced all but ring and pinion and the bearings. Also, 23 tires and a complete new set of wheels have been put on this truck in two months and 3000 miles. I test drove two similar trucks with an automatic transmission and they both were smooth as silk and just spoke with a gentleman with a 2016 model truck same as mine with auto and he stated his rode smooth. I really like my manual transmission.

 

[Dieselnerd]

It sounds like you are ready to use the lemon law and ask for a new truck.

 

[RSOUDER]

It sounds like you are ready to use the lemon law and ask for a new truck.

I think it is getting close. I was hoping not to go there.

 

[TCDiesel]

I know this is goona sound Bizarre, I changed gear lube and it seems to be gone, When I put the PML cover on back in 2013, I install Temp sensor, The Temp sensor broke (Something hit it) I decided just to change out the lube/sensor it had Schaeffer's 80/90 and had 38K miles look new when draining. Switch it to Castrol Syntrac Limited Slip 75/90w.

Its been really cold here so when I took it for a drive I only had enough time to run it up to 85MPH for a short time, the Speed Limit around here is 70...

When I go back to the Cabin next Month in MT the speeds will increase in ND/MT and I will have better results then , the truck just goona sit and be occasionally driven around the block until then.

 

[sag2]

One piece drive line here also.

 

[Ozymandias]

I find this discussions always interesting, that no one first asks if it is a wheel or driveline related vibration.
That is so easy to keep separated as it is around 4:1 in Frequency.

And as a matter of fact - vibrations are hard to trace, sometime they feel coming from the back but they are actually coming from the front. One shouldn't be to sure about the source of a vibration especially if it isn't gone after changing the supposed part.
It is totally Nonsens, sorry, to change 30!! Tires on the vehicle, that workshop really is lost in space. Helpless.

 

[Ozymandias]

.

 

[jgillott]

With the G56, don't overlook the dual mass flywheel. I chased a vibration for months and finally replaced my clutch when it started slipping with a single mass flywheel and South Bend clutch. The factory flywheel was a mess. Vibration is gone now and frankly it hasn't run this smooth in years.

Again, there are many possibilities for vibration causes in these trucks, but with a G56, you just never know the condition of that dual mass flywheel.

 

[sag2]

I find this discussions always interesting, that no one first asks if it is a wheel or driveline related vibration.
That is so easy to keep separated as it is around 4:1 in Frequency.

And as a matter of fact - vibrations are hard to trace, sometime they feel coming from the back but they are actually coming from the front. One shouldn't be to sure about the source of a vibration especially if it isn't gone after changing the supposed part.
It is totally Nonsens, sorry, to change 30!! Tires on the vehicle, that workshop really is lost in space. Helpless.

Well not really if the tires they tried were not in specification for road force. When I was still working it was not unusual to go through a bunch of tires to actually find ones that were round and in spec. When you are chasing a tire and wheel vibration you don't want to be close, you want to be perfect. But I suppose that's true for drive lines also.
I always used the vibration analyzer because it pinpoints the frequency so your not throwing the wrong parts at it. But you can pretty much tell the difference between drive line and wheel speed, but I was always amazed at the number of technicians that had no cluse what they were chasing.

 

[EDankievitch]

I had a vibration until I found a tire shop that knew what they were doing when it comes to balancing tires. The Shop Tec told me that RAM wheels are not true center on the bore they are Stud centered. You have to mount the tire on an special plate with studs that center the tire/ wheel on the balance machine. If the tire shop takes the short cut it's a crap shoot if the wheel is turning true or not.

 

[gsfitzsr]

My theory is Ram may have a bad batch of parts. The reason I say this is I put the truck on jack stands and ran it up to 70 mph (make sure to turn off traction control) and the left rear tire has some run out side to side and up and down. The right rear looked pretty good. I then took the rear tires off and ran it up to 70 mph. Both rotors had run out and the left rear caliper was rattling (I secured the rotors first). I pulled both rear rotors and did the same for the hubs. I saw movement in both hubs so I then check them both with a micrometer. The right rear was at 0.015" and left rear was 0.020" on the hub face. That's way above factory specification of 0.005". I will dig into it some more and check the new parts. Hopefully there is a fix.

Great troubleshooting! I did the same measurements on my 2018 to put into another forum on www.cumminsforum.com

My truck runs smooth and I did videos showing what I could. I ran it up to 70MPH jacked up on stands to show how little vibration there was. I then removed one rear tire and took readings the same as you did on the hub faces. My readings were below 0.005 TIR (total indicator reading). The 0.020 you measured is very high. Your on the right track!

 

[RSOUDER]

I find this discussions always interesting, that no one first asks if it is a wheel or driveline related vibration.
That is so easy to keep separated as it is around 4:1 in Frequency.

And as a matter of fact - vibrations are hard to trace, sometime they feel coming from the back but they are actually coming from the front. One shouldn't be to sure about the source of a vibration especially if it isn't gone after changing the supposed part.
It is totally Nonsens, sorry, to change 30!! Tires on the vehicle, that workshop really is lost in space. Helpless.

I knew it wasn't the tires the moment we rotated the rears to front and vice versa. The second dealership said the tires have to meet roadforce first. I have had a total of 19 new tires installed by Firestone and according to the third dealership, none have met roadforce. The last set was Michelen Defenders. At that point I believe it is either the wheel or as EDankievitch says that the tire shop doesn't know how to balance wheels. Since then, I put the wheels and tires from my 05 Ram 3500 on it and it didn't make a difference. Vibration is still there. After three closed cases from Chrysler Customer Care and three dealerships here in Florida, I decided to drive up north with this vibrating truck for 10 hours to the dealership I originally purchased it from. They did replace all the parts i mentioned with all new wheels and tires and still I have a vibration at 70 mph and up. I will say that the ride did improve "some". At that point the dealership says it is a ride characteristic of that truck. I don't think a new 2018 2500 Ram Laramie 4x4 Diesel should be vibrating at all other than a bumpy ride on rough roads. They let me drive two similar trucks and they had the same issue. Thats at least three trucks i know of that shake. A Shimmy will tear up a truck. I don't feel anything in the steering wheel or the stick shift so its hard to think of it being transmission or driveshaft. But , I could be totally wrong.

 

[gsfitzsr]

Thank you for the reply. I wish I could say the same. I have a one piece shaft from the transfer case to the rear differential. We put a vibration analyzer in different locations on the truck. The left rear makes the most vibration. It comes out at 12 HZ at 1800 rpm which translates to a bump every revolution of the tire. That could be tires, wheels, rotors, hubs, axles, bearings, ring and pinion. Dealer replaced all but ring and pinion and the bearings. Also, 23 tires and a complete new set of wheels have been put on this truck in two months and 3000 miles. I test drove two similar trucks with an automatic transmission and they both were smooth as silk and just spoke with a gentleman with a 2016 model truck same as mine with auto and he stated his rode smooth. I really like my manual transmission.

My last posting about the engine and drive shaft spinning at 1:1 ratio was WRONG! My mistake.. I did not read your manual transmission specs correctly.

The G56 spins the drive shaft FASTER than engine speed in 5th gear (0.72 ratio). So an engine speed of 1800 RPM (30Hz) outputs a shaft speed of 2500 RPM (41Hz) which in turn drives the wheels/tires at 731PM (12Hz) assuming your axle ratio is 3.42. This results in a vehicle speed of 71MPH when your run stock 275/70 R18 tires.

 

[RSOUDER]

My last posting about the engine and drive shaft spinning at 1:1 ratio was WRONG! My mistake.. I did not read your manual transmission specs correctly.

The G56 spins the drive shaft FASTER than engine speed in 5th gear (0.72 ratio). So an engine speed of 1800 RPM (30Hz) outputs a shaft speed of 2500 RPM (41Hz) which in turn drives the wheels/tires at 731PM (12Hz) assuming your axle ratio is 3.42. This results in a vehicle speed of 71MPH when your run stock 275/70 R18 tires.

You are correct about the 3.42 rear end gear ratio and the 12 hz at 1800 rpm. The tires that came stock are Firestone Transforce AT 285/60/20. The dealer I purchased the truck from in North Carolina paid Firestone to put on new Michelin Defenders on the original wheels which, also, did not meet roadforce spec. The new tires did cushion the ride some, but again did not correct the vibration. When I took then truck to North Carolina, the original dealer, to fix the problem, They swapped out the tires and wheels from another truck on the lot and now I'm back to Firestone tires. I would have preferred them to mount the Michelins on the new wheels. But I don't believe that to be the problem anyway. I assume there are others that are dealing with the same issue since the two new ones I drove at the dealer had the exact same feeling vibration at the same speed.