Worse Vibration

[M36]

Im sure the answer is out there somewhere, but I havnt found it while doing a search. Some of you are having a vibration problem around 70 mph. I made a post awhile back explaining the vibration that I have. This past weekend I hooked up the 5W and went for a drive on the freeway. At 70 mph, the pulsating vibration was extremely worse and louder while under the load of the 5W. It also created a vibration in the passenger seat that could not be felt in the drivers seat. The pulsing noise, although louder in the drivers seat was not as loud in the passenger seat. Once we bumped it up to 75, the vibration and pulsing noise stopped. This is biazarre and I am just anal enough to have something like this send me through the roof. Rattles are the worse for me.



Has anyone found the reason for this yet. I would like to fix this before our trip to AR next month.



Thanks,

Jim

 

[raychem]

only 2248 miles on the truck

I'm too upset at this time to elaborate on your possible vibration seeing as though it is 3am my time and I am too tried to type. I just returnd from Naples FL after driveing from Miami, roughly 150 miles. To my sadness. . I can tell you that I felt the vibration and this was the result. LOST 4 quarts of AFT all over the bottom of the truck and a subtantial leak from the tail section of the transmission. Judging by the fuild lost and the sound of the transmission ofter stopping and replacing the 4 quarts, I can tell you It will need a full rebuild. I'll start a new tread on this with a full explanation for everbody tomorrow... ...



Richard

 

[Prairie Dog]

Jim, is this a knock you feel mainly through the accelerator? If it is it's been discussed here before and to make a long story short, it will go away and smooth out with a a few thousand more miles.



My condolences to you Richard in regards to your recently de-parted (sorry) transmission. Keep us posted on your exploits with the dealer.



Scotty

 

[M36]

Originally posted by Prairie Dog

Jim, is this a knock you feel mainly through the accelerator?

No. I wish it was just a knock. Under the load it is a loud pulsating vibration noise that fills the inside of the truck. The vibration can be felt while sitting in the front passenger seat, but not felt in the drivers seat. However. while sitting in the drivers seat the sound is louder than it is sitting in the passenger seat. When I get up to 75 and beyond the pulsating vibration sound goes away and the truck seems to smooth out.



Without the load of the 5W, same same sensation is there, but not as loud and noticeable. The load seems to magnify the problem.



Im looking for somthing to go to the dealer with so at least Ill sound like I know what I am talking about.



Jim

 

[tcb]

mine does it also, i have the 47re and think it is just a quirk of the transmission, no problems yet with 9k miles, but it is very annoying at 75 mph so i just avoid that speed as much as i can. i do think it is transmission or transfer case if you do get it looked at post what the dealer had to say. i may need to see mine if it turns out bad.

 

[Blakers]

Try to isolate the problem. Shut the engine off while going downhill and see if it is engine related or drivetrain related. Try coasting with the transmission in gear and the clutch in and then put it in neutral and see what that does. You should be able to isolate and determine whether it's coming from the engine, transmission or other drivetrain. Maybe even tires.



Blake

 

[Boonieman]

My truck does the same thing from about 65 mph to 72 mph. At 72 everything quiets way down and the truck gets in a groove. It really doesn't feel like a tire out of balance, but I believe it could be something in the running gear out of balance. It's not severe enough yet for me to worry about, just annoying, but it is noticeable and I'm paying attention to it. Then again, I had an old Chevy truck way back with the old bulldog 4-speed heavy transmission. That thing made all kinds of racket and vibrations and had over 200,000 miles on it when I sold it and I never touched the transmission or engine..... and I consider this Dodge/Cummings/6 speed combo to be quite a cut above that old Chevy and I guess that's in the back of my mind... . or maybe it's just hopeful thinking.

 

[M36]

Here is a report. Took it and the 5W back out onto the freeway this morning and got the same vibrating/noise sensation right at 70. I took it to 75, let off the accelorater, still in Drive, and the noise dropped, but was still faintly present. The noise/vibration stayed with the AC on and off. However, when at 75, putting the shifter into neutral, the noise disappears completely, but comes back after putting it into drive.



Sounds like some kind of a transmission quirk. Driveline maybe? I think the noise going away while in neutral, rules out the tires and wheels.



Your thoughts?



Jim

 

[Steve M]

M36, Can I assume you have 3. 73 gears? My truck has the 2100rpm drone and vibration at 64-68mph with 4. 10 ratio and automatic. I had a drive shaft vibration along with the drone. The dealership swapped the shaft with another truck and cured the drive shaft vibration. It started very slightly at 45mph, was almost an attention getter at 55mph and at 65 was competing with the engine drone. I couldn't tell what was behind me in windshield rearview mirror from the vibration. It was a pulsating vibration that was present with the engine off in neutral coasting down from 70mph to about 45mph.

 

[raychem]

Sorry I have not yet posted the problem with my truck but until tomorrow (Tuesday) I really don't know what happened but I have some idea (dealer has not looked @ the truck yet... long weekend). Anyways. . I bought the truck out of state and drove it back home 1300 miles, When ever I would go over 90 MPH I would get a droning sound and a vibration. Since I was not familiar with the truck, I thought it was probably tires. This thought quickly came to rest as I got stranded by a leaking tail on the transmission as mentioned before. Now I feel that since this occurred with speeds over 90 MPH, I'm beginning to feel that my drive shaft was the culprit since as long as I did less that 90, I never had a vibration. This would also explain that when I did over 100 MPH, the vibration would go away. I'll will tell the dealer about the drive-shaft tomorrow and I'm looking at this in a positive way know... Time to call DTT for a full transmission ... again since I love the way their transmission ran on my 97. If any body here has experienced the same problem and could give me some suggestions on the vibration or how you took care of it, please let me know.



Thanks,

Richard

 

[M36]

Originally posted by raychem

M36, Can I assume you have 3. 73 gears?

Yes I do. And it is going into the shop this week or Monday and Ill let everyone know what happened.



Cheers,

Jim

 

[91W350]

Jim, Keep us posted. Mine vibrates from 70 to 80, the worst in the area of 72 to 78, right where I like to drive! I have been running 70 and the difference in fuel mileage is nice. I am approaching 8K now and would like to get it fixed. I thought it was the front drive-line, had it replaced. The vibration is still there, but not quite as bad. I can fix it completely by removing the front shaft, that's worse than locking in hubs when you need four wheel drive though! I would really be upset if the rear sinks and I have to lay in the mud to put in the front shaft!

 

[PCline]

Jim



I had a similar problem with my truck and it came down to driveline angles.



I have a 4X4 longbed though and it's got a two piece rear driveline. I think your truck only has a one piece driveline.



The pulsating feeling you describe is typical of driveline angles. So is the fact that is only happens at certain speeds. Also, the fact that it gets worse with load is consistent. Two things happen, 1) the suspension squats and the angle change slightly and 2) more torque is being driven through the drivetrain causing the axle to wrap and modify the angles even more.



Have your dealer put a vibration analyzer on the output of the transfer case and go for a drive (preferably with trailer in tow). If it's the driveline you should be seeing a vibration frequency of around 47 - 48 Hz (3. 73 differential).



Don't let the dealer tell you he checked the angles and everything is OK. Go to your local trusty 4X4 shop and have them check it. I found that they've dealt with way more driveline angle problems than any dealer. Also, the manual procedures and figures for the driveline angle checks are misleading and in part incorrect. So I don't think even a conscientious tech will get it right unless he has had experience doing it before. It's well worth the $ at a 4X4 shop.

 

[Steve M]

We took a 400~ mile trip this weekend and discovered a new vibration. At 75mph my truck developes a steady deep vibration. Just for kicks I tried it sitting still in neutral. Same vibration at 2600rpm. It does it in park, with or without the a/c on and seems to come on like a timing change or something right at 2600rpm. I'm thinking maybe torque converter or engine vibration damper. I'm not real anxious to take it to the dealer for service after the last fiasco over the driveshaft.

What scalds my juevos the most is, the '01. 5 that I traded for it was flawless. Except for the normal 2100rpm drone and idle vibration, it had no driveline vibration at all from 0-85mph. Never had it faster than 85.

 

[DBVZ]

Raychem,



I just read through this thread, and noted your truck had just 2248 miles on it when it came apart. Then I read you drove it 1300 miles after purchase to get it home, at speeds of 90 - 100 MPH at times. It seems to me I read something about a breakin period, particularly for the axel gears. Others on this site advocate driving it like you stole it, right from the start (which seems to fit what you were doing). Personally, I don't plan to take my truck up to 100 MPH at any time, though I can see it would help identify imperfections, and could cause a failure in anthing that was not up to the stress. I guess I am wondering if running it that hard right off the lot is reasonable.

 

[raychem]

DBVZ,



I'm sorry if you got the wrong impression... when I drove it home, I was between 65 and 85 MPH varying the speed and not staying constant. But also on the trip home I pushed it to 95 once to pass a car, I felt the vibration and though it was the tires. . new truck and don't know how it behaved yet. Then for the last 700 miles or so I have babied the truck never exceeding 80 and no I did not drive the truck like I stole it. When I set out on my trip on Friday, I had roughly 2100 miles on the truck and I feel that the truck should run without any drive line problems and should be broken in at 2100 miles( not the motor of course)... including the rear end. Reading some of the earlier posts... I feel the drive shaft is not balanced correctly and at the speeds I was traveling at. . I hit a sour spot in the drive line and it caused the seal to fail. I know these truck have some problem that still must be worked out and i admit it. . I still love my dodge. . I'm just a little upset that I still have not made the first payment.







Richard

 

[91W350]

Hey Richard, if payments are your thing, I'll send you a page or two out of my booklet! Actually, I would be happy to send you the whole book if you are volunteering. I had everything paid for and then Dodge came along with this cool quad cab, rattle package, four wheel drive, I thought I had to have one! I would hate to be without now. Glen

 

[raychem]

Hey ggsoldan, I should of said that I have not made my first payment yet... . not that I wanted to take over anybody's payment for them!!!!



Richard

 

[91W350]

Richard I was just sure you wanted to help somebody out! Sure is a cool ride though! I love mine, I do not go anywhere in particular, and still drive it over 100 miles a day average. I am addicted... Glen

 

[raychem]

Ggsoldan, I agree with you 100% I still love my ride and to me it is one of the nicest trucks on the road... I drive a 3500 drw just because it is one of the baddest looking trucks. . oh and it has all the pretty little lights! Occasionally, I also carry 100 lbs of dog food in the bed, about once every 2 months or so . Sorry about the payments thought Glen, maybe if I hit the lottery i'll make some for you!