Driveline vibration at highway speeds
#1
Driveline vibration at highway speeds
I have been fighting a vibration which I first noticed in December, about a month after I had my 4.10s redone by a dealer due to a bad install at a speed shop. The vibration occurs at highway speeds (55+) and increases in frequency as the car speeds up. By 75+ it's noticeable even on terrible roads. It's in the floorboard and there is an audible rumble associated with it. It seems to worsen once the car gets warm and is worst when cruising although present on both acceleration and deceleration.
These are FRPP 4.10s dealer installed, full bearings, cups, etc. At first they were silent, but over the past few months they developed a slight whine and howl, so last week I returned and the dealer installed set #3. Again full bearings and cups were installed and they were not able to get them 100% silent. After a call to the Ford tech line they ended up installing a new axle housing due to the original being warped? In any case I now have the quietest set of gears I have ever "not heard".
Problem is the driveline vibration persists. I know its not a tire (I swapped wheels form another known good car), I have new gears, new axle housing and what I think is a perfect install all within spec. On previous visits drive shaft balancing was attempted with the "worm clamp" procedure and the driveline angles were checked and then corrected with Adj. UCA and Panhard bar (I have Steeda Ultra-lite springs and FRPP dampers).
The dealer is mod friendly but I'm starting to worry about them giving up and claiming it's due to the suspension modifications. I had the UCA professionally installed and the pinion set at -2 degrees and it made absolutely no difference. Nothing's made any difference so far, the darn vibration just persists through everything we try. What the heck else could be the cause here?
Tim
These are FRPP 4.10s dealer installed, full bearings, cups, etc. At first they were silent, but over the past few months they developed a slight whine and howl, so last week I returned and the dealer installed set #3. Again full bearings and cups were installed and they were not able to get them 100% silent. After a call to the Ford tech line they ended up installing a new axle housing due to the original being warped? In any case I now have the quietest set of gears I have ever "not heard".
Problem is the driveline vibration persists. I know its not a tire (I swapped wheels form another known good car), I have new gears, new axle housing and what I think is a perfect install all within spec. On previous visits drive shaft balancing was attempted with the "worm clamp" procedure and the driveline angles were checked and then corrected with Adj. UCA and Panhard bar (I have Steeda Ultra-lite springs and FRPP dampers).
The dealer is mod friendly but I'm starting to worry about them giving up and claiming it's due to the suspension modifications. I had the UCA professionally installed and the pinion set at -2 degrees and it made absolutely no difference. Nothing's made any difference so far, the darn vibration just persists through everything we try. What the heck else could be the cause here?
Tim
#2
Uh.."balancing the drive shaft with work clamps"? No way can that work reliably!!!
Sounds to me like your driveshaft is out of balance. It may have been dropped during the last gear install, or one of the prior ones.
If it's still under warranty, have them replace it.
Worst case, get an aftermarket one (like from shaftmasters) or find a used one.
Also, they might have put it on in the wrong location this last time.
Or they should try rotating it on the pinion flange (moving it around/rotating it so the driveshaft mounts to different holes); that fixes a lot of the problems.
My stock driveshaft had a vibration from day-one around 65 mph; replacing it fixed it.
Sounds to me like your driveshaft is out of balance. It may have been dropped during the last gear install, or one of the prior ones.
If it's still under warranty, have them replace it.
Worst case, get an aftermarket one (like from shaftmasters) or find a used one.
Also, they might have put it on in the wrong location this last time.
Or they should try rotating it on the pinion flange (moving it around/rotating it so the driveshaft mounts to different holes); that fixes a lot of the problems.
My stock driveshaft had a vibration from day-one around 65 mph; replacing it fixed it.
#4
Fortunately it’s still under the extended power train warranty and everything that's been done so far has either been covered by Ford or the Dealer. I'm headed down there tomorrow morning to return a rental; I think I'll having a chat with the service manager about the driveshaft while I'm at it. If that's the problem it's just a matter of time before the gear noise returns or worse.
Tim
Tim
#5
Uh.."balancing the drive shaft with work clamps"? No way can that work reliably!!!
Sounds to me like your driveshaft is out of balance. It may have been dropped during the last gear install, or one of the prior ones.
If it's still under warranty, have them replace it.
Worst case, get an aftermarket one (like from shaftmasters) or find a used one.
Also, they might have put it on in the wrong location this last time.
Or they should try rotating it on the pinion flange (moving it around/rotating it so the driveshaft mounts to different holes); that fixes a lot of the problems.
My stock driveshaft had a vibration from day-one around 65 mph; replacing it fixed it.
Sounds to me like your driveshaft is out of balance. It may have been dropped during the last gear install, or one of the prior ones.
If it's still under warranty, have them replace it.
Worst case, get an aftermarket one (like from shaftmasters) or find a used one.
Also, they might have put it on in the wrong location this last time.
Or they should try rotating it on the pinion flange (moving it around/rotating it so the driveshaft mounts to different holes); that fixes a lot of the problems.
My stock driveshaft had a vibration from day-one around 65 mph; replacing it fixed it.
Tim
#6
you running factory wheels and were the other wheels you tried the same? i know some folks put on aftermarket wheels and forget to remove those stupid snap rings, that can sometimes cause a vibration since the wheels don't get to sit flat.
#7
Tim
#9
Tim
Last edited by tdbrown75; 03-03-2011 at 02:44 PM.
#10
Your problem is most likely driveshaft balance. An aftermarket driveshaft will help as they are balanced better. However you may still wind up with a vibration even after the shaft. It will just occur at much higher speeds. The better the driveshaft balance, the higher up the speed the vibration sets in will occur.
Even though your pinion angle has been reset, I've seen cars that are still sensitive to this. I would try .5 to 1.5 negative. Somewhere in there I am willing to bet the issue will improve. Probably wont improve significantly until you get a better driveshaft though.
Even though your pinion angle has been reset, I've seen cars that are still sensitive to this. I would try .5 to 1.5 negative. Somewhere in there I am willing to bet the issue will improve. Probably wont improve significantly until you get a better driveshaft though.