Gearbox Or Cv

[Dr Pete]

I asked a question earlier on about a whine from the gearbox on my Mk1 1.9TDi Galaxy. At the time this was because I had been told by my garage that that was where the problem lay although I had taken it in because I thought I had a problem with a CV joint.

 

I have been driving the car and the noise has got much worse and now sound a bit like driving over a rumble strip at high speed. However, I have noticed that the pitch of the noise changes with the speed of the car not the speed of the engine and in fact is still there if when the clutch is in or the gearbox is in neutral. Also the sound seems to be worse when going in a straight line or turning left but better (but not absent) when turning right. My garage is usually very good and never does anything that doesn't need doing. So is this likely to be teh gearbox or ist it a CV joint?

[familyman]

the fact that noise changes when cornering would point to cv

[Dr Pete]

But could it still be the gearbox? I am going to have to argue the point with the garage and don't want to do so if it could still be a gearbox problem. I don't want to have to pay for a new gearbox if I can merely pay for a CV joint.

[zeplin43]

i would say outer cv joint is more comon to fail and seems to fit the discription you give. The issue is do you trust the mecanic who is going to fix the car.

[Dr Pete]

I trust the garage and the owner who does some of the work himself. I've never had any problems with them, the work is always done really well and if I there are any problems they're happy to discuss them and sort them. But if I've laid out

[sepulchrave]

It sounds like the differential to me (in the gearbox), I think the whole CV joint thing is a red herring, mine went badly and it certainly didn't whine!

 

The differential can be treated as a separate entity to the gearbox in terms of repair but the gearbox still has to come out. Most garages prefer to fit a recon box since there's no actual repair work involved for them and the part is guaranteed.

 

If it's the diff I'd be tempted to fix it myself since there are no special tools required to change a diff, and it may be that only new bearings and seals are needed.

[Dr Pete]

It sounds like the differential to me (in the gearbox), I think the whole CV joint thing is a red herring, mine went badly and it certainly didn't whine!

 

The differential can be treated as a separate entity to the gearbox in terms of repair but the gearbox still has to come out. Most garages prefer to fit a recon box since there's no actual repair work involved for them and the part is guaranteed.

 

Thanks for the info.

 

If it's the diff I'd be tempted to fix it myself since there are no special tools required to change a diff, and it may be that only new bearings and seals are needed.

 

I din't know that there was a diff in the gearbox! To be honest I thought the CV joint did the same thing. Sadly I don't think that I could remove the gearbox myself so it would have to go to this small garage I use.

 

Initially the noise made was a whine but it has now gone to more of a rumble. A bit like running along the rumble strip on a mpotorway.

 

As the gearbox has to come out is there anything that would definitively identify it as the diff?

[sepulchrave]

Well wheel bearings are another possibility, jack the car up and grip the roadwheel firmly top and bottom and try to rock it. You can then cross the CV joints off a very short list by simply grabbing each driveshaft and trying to shake it, if you can then the joint has had it! Otherwise it's in the gearbox.

[Dr Pete]

Well wheel bearings are another possibility, jack the car up and grip the roadwheel firmly top and bottom and try to rock it. You can then cross the CV joints off a very short list by simply grabbing each driveshaft and trying to shake it, if you can then the joint has had it! Otherwise it's in the gearbox.

 

Sorry, if I'm being a bit thick but If it is in the gearbox how can I decide that I need a new diff or a whole new gearbox?

[sepulchrave]

You won't be making that decision, since you aren't doing the work! Like I said:

 

"Most garages prefer to fit a recon box since there's no actual repair work involved for them and the part is guaranteed."

 

This obviously includes the differential. Ok?

[Dr Pete]

You won't be making that decision, since you aren't doing the work! Like I said:

 

"Most garages prefer to fit a recon box since there's no actual repair work involved for them and the part is guaranteed."

 

This obviously includes the differential. Ok?

 

As the Galaxy is a 1997 Mk 1 I do not think that the gearbox or differential will be under warranty and so there will be a big differnce in price between fixing the diff or buying a recon box. If I can give the garage a sound reaon for the problem being a diff then they will at least look. I wasn't being funny when I said that I didn't know if I was being thick. I used to do all of my own repairs 30 years ago but modern cars are so complex now and they never cease to amaze me.

 

Pete

[sepulchrave]

Unfortunately garages no longer employ proper mechanics, they only have fitters.

 

I would be VERY surprised if your garage are prepared to remove the gearbox, strip it, replace the diff, reassemble and refit.

 

As I implied there is an element of uncertainty which is negated by replacing the entire gearbox with a guaranteed service exchange unit.

 

You are correct; you have no warranty unless you recently bought the car from a dealer. However a gearbox today is remarkably similar to a gearbox of 30 years ago!

 

Make the simple checks I have suggested and visually inspect the diff housing for any oil leakage; when the bearings fail the oil seals generally follow causing some visible loss of gearbox oil (caught in the undertray).

[Dr Pete]

Unfortunately garages no longer employ proper mechanics, they only have fitters.

 

I would be VERY surprised if your garage are prepared to remove the gearbox, strip it, replace the diff, reassemble and refit.

 

As I implied there is an element of uncertainty which is negated by replacing the entire gearbox with a guaranteed service exchange unit.

 

You are correct; you have no warranty unless you recently bought the car from a dealer. However a gearbox today is remarkably similar to a gearbox of 30 years ago!

 

Make the simple checks I have suggested and visually inspect the diff housing for any oil leakage; when the bearings fail the oil seals generally follow causing some visible loss of gearbox oil (caught in the undertray).

 

 

Many thanks for all of your help. I think that I misunderstood when you said that the diff was a separate entity but required the removal of the gearbox as I assumed that it was fitted perpherally and wouldn't require the stripping down you mention. I assume therefore that if I get a secondhand or reconditioned gearbox It will have the diff in it.

 

Pete

[tim-spam]

Yes it will.

 

As regards the noise being speed dependent, this points to either the differential or the gearbox output shaft - either way, a recon. gearbox will fix it.

[sepulchrave]

Have you tried www.lastword.com/delurk? :wacko:

[doubleone5555]

hi. i am hoping you can enlighten me a little. i have a 98 tdi and am getting the same noise at the same speeds, however i have an auto gear box you do not say if your is. can you let me know? thanks. doubleone

[nohomers]

Be careful that its not popped/ sheared an engine mount, my sharan had 3 of these, sounds exactly as you describe. Alythough it obviously isn't apparent when you are stationary. Try holding the engine on the top n rocking it forwards and back, also look under the car at the panels around the drive shafts if there has been any rubbing, you'll see it. Edited October 7, 2007 by nohomers