Strange Noise

[tommyturbo]

So I am trying to figure out where this is comming from...and what it is.
The car is a 88 SHelby Z, turbo II A-555, stock in every way.

The drive axles on both sides were replaced recently, by a shop, since the boots finally gave out. I noticed since I got the car back that in lower gears when accelerating with lots of boost it feels like a subtle vibration and a consistent rubbing noise that never gets louder or quieter, and never changes tone, even though the engine does get louder while accelerating, thats the best way I can describe it. It doesn't sound like any kind of engine noise, almost like the noise of disc brakes dragging a little...but much louder.

I thought it might be the front end lifting and the tires breaking loose, but it never did this before the new axles. I also thought it might be the clutch, but it doesn't act like it is slipping and has less the 3000 miles since it was replaced. It also feels a bit slower, but that could just be my imagination.

OPen to idea of things to look for.

[85boostbox]

wheel bearings, calipers hangin on you. Any kind of brake smell or is there and kind of distinctive pulling when you let go of the steering wheel while cruising is there any time it doe it worse or it gets louder. any specific part of the car that is coming from. and oh yea one other thing is what kind of lubrication did they put back in your transmission and you might want to make sure that they put lube back on it too

[tommyturbo]

no bad smells, freshly aligned, no pulling, drives great, no wheel bearing noises and never made this sound before the new axles, and they used the correct 5w-30 motor oil. Only time I hear this noise is under heavy throttle accelerating in 1-3....not sure i hear it in 4th or 5th. SOund is always same volume, tone etc, never changes in corrilation to road speed, engine speed etc, only does it under heavy accel.

[Abkshelby]

Make sure your engine mounts are ok. Sometimes when new axles are installed the engine needs to be recentered. If this noise was not there before the new axles have moved something. I'd be willing to bet they put a different style of axle in since about 4 different makes of axles were used for these cars.

[tommyturbo]

If they did use a diffeent sytle, will that be a problem in the long term? They were new, not rebuilt. I'll take a look at the mounts and see.

[Abkshelby]

It's not a problem if they did not put the same type ones back in. If they are new axles though they are likely made in China. Hopefully not but if they are plan on them failing quick. I've known several people that have had issues with China axles. And the choices are getting worse.

[tommyturbo]

I am not sure where they were made....but will ask. I just know they are new and not rebuilt.

I looked at the mounts, although I didn't see anything really odd, compared them to my other car.