Mustang Trans/Rearend Problem... HELP NEEDED

[Systemax302]

Okay, where to start, sorry this might be a little bit of a long read, but I need to gather some very educated information. The car is a 95 GT (5.0) w/ a 5 speed (t5). The Trans is factory stock to the best of my knowledge and if this is true it would have about 55k miles on it. The car has a small blower and bolt ons and its making 280 RWHP and 320 ft/lbs of torque, so it is making roughly 100HP over stock. The car has really never been driven really hard and/or drag raced and its never been on anything besides street tires. No drag radials or slicks.

THE PROBLEM(s)

This started mainly a couple days ago pretty much right after the car was lowered. Car got new shocks and struts all around and an Eibach Pro Kit.

Shortly after, probably within 10 miles of driving I noticed a clunking/popping sound coming from the rear of the car. At cruising speed its fine and even downshifting and hard acceleration seems fine and business as usual to me and I notice everything w/ my car. This occurs when starting in first gear and when going over a bump at low speeds say like the edge of a driveway. Also if you let the car coast in low gear at low speed and it will naturally want to kind of buck a little it seems harder than usual, louder, and feels like its more loose and sloppy in the back. Also when your coming to a complete stop when the weight of the car shifts you can feel it in the rearend. All the gears in the trans work, but the trans does have some buzzing sounds coming from it intermittently, mainly while coasting in 5th gear and the 4th gear synchro isn't perfect anymore either.

WHAT I TRIED TODAY

I first hoped maybe there was a suspension component loose from the install, but I went through the whole suspension today and there was nothing loose or out of place. There is some play in the driveshaft and when I move it by hand I can hear the clunking/popping sound Im hearing while starting in first gear so Im pretty positive this is the cause of the noise. You also can hear the noise from the center of the vehicle when pushing in on the top outside edge of the rear tires while the car is sitting on the ground.

QUESTIONS

Is the car alright to drive? What are the potential risks?

What do YOU think the issue is? Driveshaft? DS yoke? Rear end?

What do you think the best long term solution to this is?


Feel free to post up any and all information you have about this. I need all the help I can get at this point ow:

 

[2004boss]

is the rear end a locker most likely not your noise but what the hell. Im curious about the trans noise in 5th my car does the same when its cold

 

[hangem high]

U-joint or upper control arm bushing making noise. if it is the u-joint, fix it sooner then later...
5 gear noise, worn gear or bearing in the trans. you can drive that for a while.

Make sure the driveshaft is not hitting anything in the tunnel.

 

[Systemax302]

is the rear end a locker most likely not your noise but what the hell. Im curious about the trans noise in 5th my car does the same when its cold

Nope its not a locker its a factory 8.8 w/ 3.55 gears in it.

U-joint or upper control arm bushing making noise. if it is the u-joint, fix it sooner then later...
5 gear noise, worn gear or bearing in the trans. you can drive that for a while.

Make sure the driveshaft is not hitting anything in the tunnel.

Im HOPING its only the U Joint on the end of the driveshaft and not the rear end itself, but Im not positive so Im trying to figure it out. The driveshaft clears fine and isn't coming in contact w/ anything under the car.

I know what the noise in the trans is I was just trying to give everyone ALL the info I had available.

 

[Sean]

Put the car on a hoist and remove the driveshaft. Try to shake the pinion side to side or top to bottom and in and out. If it move in any of those directions the crush sleeve may have fialed or you have a bad pinion bearing.

If that checks out It would not be unheard of to have a noisy T5 with a cluster gear bearing or input bearing fialure making alot of noise.

Check the pinion bearing first.

Nope its not a locker its a factory 8.8 w/ 3.55 gears in it.



Im HOPING its only the U Joint on the end of the driveshaft and not the rear end itself, but Im not positive so Im trying to figure it out. The driveshaft clears fine and isn't coming in contact w/ anything under the car.

I know what the noise in the trans is I was just trying to give everyone ALL the info I had available.

 

[Systemax302]

Put the car on a hoist and remove the driveshaft. Try to shake the pinion side to side or top to bottom and in and out. If it move in any of those directions the crush sleeve may have fialed or you have a bad pinion bearing.

If that checks out It would not be unheard of to have a noisy T5 with a cluster gear bearing or input bearing fialure making alot of noise.

Check the pinion bearing first.

That would be AWESOME, but I don't have a lift or access to one.

I know the bearings in the T5 aren't in the best shape, but I also am pretty damn sure that has nothing to do w/ the rear end issue Im having. The trans Im not worried about. It will live for a while in its current condition, but the rearend/driveshaft issue is what Im truely WORRIED about right now.

What would be the risks of driving the car in this condition? I would like to make it out to WW again probably Saturday, but I don't want a catastrophic failure out there either...

 

[Systemax302]

is the rear end a locker most likely not your noise but what the hell. Im curious about the trans noise in 5th my car does the same when its cold

Thanks, you've been repped...

U-joint or upper control arm bushing making noise. if it is the u-joint, fix it sooner then later...
5 gear noise, worn gear or bearing in the trans. you can drive that for a while.

Make sure the driveshaft is not hitting anything in the tunnel.

Thanks, you've been repped...

Put the car on a hoist and remove the driveshaft. Try to shake the pinion side to side or top to bottom and in and out. If it move in any of those directions the crush sleeve may have fialed or you have a bad pinion bearing.

If that checks out It would not be unheard of to have a noisy T5 with a cluster gear bearing or input bearing fialure making alot of noise.

Check the pinion bearing first.

Thanks, you've been repped...

 

[Sean]

A jack anbd jackstand would be fine. Get the wheel off the ground and driveshaft out. If the pinion has orbital play then do not drive the car. Catching it early will save the gearset from destructions. Maybe just a set of bearings if it is bad and you could be just fine.

That would be AWESOME, but I don't have a lift or access to one.

I know the bearings in the T5 aren't in the best shape, but I also am pretty damn sure that has nothing to do w/ the rear end issue Im having. The trans Im not worried about. It will live for a while in its current condition, but the rearend/driveshaft issue is what Im truely WORRIED about right now.

What would be the risks of driving the car in this condition? I would like to make it out to WW again probably Saturday, but I don't want a catastrophic failure out there either...

 

[Systemax302]

A jack anbd jackstand would be fine. Get the wheel off the ground and driveshaft out. If the pinion has orbital play then do not drive the car. Catching it early will save the gearset from destructions. Maybe just a set of bearings if it is bad and you could be just fine.

Checkout MAGS post in the thread of mine in the pub and see if you think this is a potential issue... Im thinking that it is given the timeframe in which this noise started and the fact that my situation seems IDENTICAL to his.

 

[Sean]

Would you rather geuss or find out. Not trying to be rude but you should at least get under the car and check things out.

Checkout MAGS post in the thread of mine in the pub and see if you think this is a potential issue... Im thinking that it is given the timeframe in which this noise started and the fact that my situation seems IDENTICAL to his.

 

[Systemax302]

Would you rather geuss or find out. Not trying to be rude but you should at least get under the car and check things out.

No its cool I see your point as well, no offense taken. I'll keep you posted. I would like to tear it down and findout for sure, but I simply don't have the time or place to do it right now... Kinda backed into a corner.

 

[SVTSINR]

I would retorque all control arm bolts at ride height.

1) Put the car on jacks leveled.
2) Loosen the control arm bolts and retorque to spec.

 

[Systemax302]

I would retorque all control arm bolts at ride height.

1) Put the car on jacks leveled.
2) Loosen the control arm bolts and retorque to spec.

It was a bit of a bitch getting the control arm to line back up after it was dropped down so this could also be a potential issue... Would you just put stands under the rear axle and let the weight of the rear of the vehicle fall onto them or lift the front end up as well?

 

[2004boss]

I would lift the front as well

 

[SVTSINR]

It was a bit of a bitch getting the control arm to line back up after it was dropped down so this could also be a potential issue... Would you just put stands under the rear axle and let the weight of the rear of the vehicle fall onto them or lift the front end up as well?

I put a jack stand under each front control arm and then jack stands under the axle. This is the easiest for me to get the correct ride height. Or if you had four cinder blocks you could give that a try also. Jack stands are lighter though...

 

[igotaneed4speed]

Did you change your pinion angle after lowering the caR?


The wrong pinion angle can make it sound like someones back there with a hammer beating on the rear end...


Also since the car was lowered the slip yoke with now be closer to bottoming out(deeper in the tailshaft of trans).

You should makes sure you have sufficent room for the suspension travel not to cause the Driveshaft to push the slip yoke far enough that it bottoms out on the tailshaft or the output shaft.