V8 Auto - Strange Noises

M

Madalicesdad

New Member
After thinking to myself yesterday how well my V8 Auto has been running, today it decided to pull a trick.

It started fine this morning, but within a mile I noticed a whining noise. I put this down to a damp alternator/steering pump belt, but by the time I got to work (8miles/30mins drive), it was quite noticable and obviously not a belt.

On the move, the whining occurs in first gear (it disappears when shifting to 2 and reappears on the downshift to 1) but is not there when stationary in gear 1. However, the noise is present when stationary in P and N.

I haven't checked the fluid levels yet (will do so at lunchtime) but can anyone suggest what the problem may be.

Mike :(
 
Has the fluid turned brown since the noise appeared?.
It does sound like it could be the brake bands as you say.
How old is the current box fluid?
You could try changing the fluid + filter and keep a close eye on the new fluid's colour and any box noises. If the new fluid darkens in colour rapidly and the noises continue/get worse, then best not to use the car until its sorted

If the worst came to the worst an auto box rebuild isn't horrendously expensive. Especially if you dont let it get any worse in the mean-time.
 
To be honest, since I changed the head gaskets in August, it's been running so well, I've not had much need to lift the bonnet so don't know exactly when it started degrading. The fluid has been in since I bought the car 7 years ago, but back in August, it was clean and has never needed topping up.

Can the bands be usefully adjusted without removing the box?

In the mean time I'd better get my other car running !

Mike
 
The bands can be adjusted with the box in the car, but I'm not sure it would help much.
If the bands needed adjusting that badly previously you probably would of noticed some heavy/clunky/slow shifting. Sound more like the bands are breaking up, through either age or maybe fluid contamination.
Could be worth a try adjusting them if your also changing the fluid. I'm sure the correct procedure is in the repair manual.
 
mike - sounds similar to what happened to me back in january. Noise was present nearly all of the time but car had drive for about 34 miles then lost it once of twice, managed to drive back home gently next day with no problems but loosing drive just got worse - I managed to get a replacment box from a scrap car (not really a good idea as it was unknown) - the original box was stripped by a specialist and found to be in good overall condition - just the friction materials u/s. The second hand box I put in was also noisy in a different sort of way but some good molyslip (with no PTFE) has made it a good bit quieter, but I'm not 100% convinced. A few more miles yet as I have a rebuilt cost of £475+vat for the box thats in bits... If you look on ebay you should find the PTFE - its worth a shot>>> here is the ebay store http://stores.ebay.co.uk/id=104127640&ssPageName=STRK:MEFS:MESST
 
£475+VAT!!!! I'll try a drain and refill first, and add some Molyslip!

There's been no problems losing drive (yet?) so hopefully any damage done can be limited. The box was a recon unit fitted not long before I bought the car so it's done less than 20k miles so hopefully (apart from the whine) should be in good nick.

Mike
 
Thanks to Ebay I have managed to get a secondhand BW65 box to replace the whining one with the dirty fluid.

According to the workshop manual, it is not possible to remove the fluid from the torque converter. As the fluid is contaminated, I want to do this when I change the box, so can it be done by:
a) sucking/siphoning it out, or
b) removing the converter assembly and draining it

Assuming the fluid has been removed, how do you refill the converter? Is it fed from the pump in the gear box, or should it be filled before the box is fitted to it?

Answers to these questions and any other advice regarding swapping the box will be greatly received. :)

Mike
 
Probably best and easiest to remove the torque converter when the old gearbox is out of the way and then drain as much of fluid as possible from it. The converter should refill itself when you put the new fluid in, though you could try filling it before refitting.
Do a couple of drain & refill's with new fluid after running the car to ensure its as clean as possible throughout.
 
I eventually got the box off. It's never as easy as the manual implies - there's no mention of the foul between the starter motor 'cover' and the transmission tunnel, and no matter how hard you pull/push/lift/swear it won't come out unless you rotate it! (That's a tip if anyone else is trying this job. The other big tip is do not underestimate how much fluid will leak out even if you think you've drained the box fully. Get a lot of newspaper before you start).

I removed the torque converter, poured as much fluid out as possible (at least a pint) and then sucked over 400ml of fluid out with a Mityvac. Even then I poured another cupful over myself when replacing it. Glad I didn't rely on flushing alone to remove the dirty fluid!

There's a slight problem as the box supplied is from an SD1 so I've had to swap the extension housing and flange, but all looks good so far.

Any tips how to replace it on my own, armed only with a trolley jack and what strength I have left?

Mike
 
Forget the shredded wheat, try a few glasses of red wine! After about 1/2 hour of trying, just before I was going to give up, somehow it 'fell' into place. I'd love to be able to share the secret of single handed gearbox replacement, but it was pure luck. It is possible though.

I'm on the home straight now and fingers crossed, it will be back on the road this weekend.

Mike
 
On other vehicles I have heard of using the pipes that run to the oil cooler in the rad as a means of replacing all the fluid. You feed the outbound pipe to a bucket to catch the old fluid, and you put the inbound pipe into a container of new fluid. Then start the engine, the internal pump in the autobox will pump out the old fluid and suck in the new.

I have never tried this myself so cannot vouch for the results but it does make sense, and should help to replace all the fluid.

Richard
 
It imagine it would do a good job of replacing the fluid in the box itself (assuming each gear was selected in turn to flush the old fluid out of all the various drillings and servos), but having now seen the design and the way the torque converter is filled from the pump, I don't think this method would replace all the fluid in the converter.
Mike
 
I got it all back together, started up, checked gear selection (which seemed ok) and reversed out of the garage.

I then found there are no forward gears! There is a slight drag forwards but not a positive engagement. Before I condemn the box, are there any adjustments that can be made (brake bands or down shift cable) that could affect it?

I hope so as it's going to be a right s0d to get it back on the ramps without forward gears!

(edit) I've had a read through the manuals and I think it could be the front clutch. Can anybody confirm/deny this as a possible cause?


Mike
 
Put a bit more fluid in it. I had a similar problem when I fitted my box after replacing the forward clutch. I over filled by about a pint, and it started working fine and has done for about 5 years.
 
Mike How did you get your car high enough off the ground to get the box out ? I find my stomach gets in the way when I'm working under mine. Did you use a jack to raise the box up?
I've got ramps stands and a medium size trolley jack and I need to drop the box on my 3500s to change the clutch
Dave
 
Dave
I managed to get an auto box out with the car on standard ramps, I was able to get a trolley jack under the car to support the box, but I had called on a friend to give me a hand - helps when you let the back of the box down on the jack to have someone who can keep an eye on how close the fan is getting to the radiator etc!
 
I have an inspection pit* which helps access for undoing bolts and leverage for pulling/pushing it, but the box came out with the car on ramps armed with a trolley jack. Once off the car I dropped it off the jack onto a sheet of chipboard and slid it out forwards.

The problem I had was that the boss on the bell housing near the starter motor that fouls the transmission tunnel (manual boxes may be different). I found that undoing the engine tie bar helped because as you drop the rear of the engine/box it pulls the front of the engine towards the left and hence the rear to the right which closes the gap by the starter motor. Removing the tie bar allows the engine to be pulled sideways a bit. Also remove the shroud at the top of the radiator to stop the fan hitting it.

Getting it back on would have been awkward without the pit (because of the foul), but not impossible.

Good luck.


Mike
* If you do dig a pit, make sure it's positioned so there's enough room to get into it with the car in position (it wrecks your trousers sliding under the car on concrete to get in and out), and waterproof it properly (dropping in to it and finding 6" water is not pleasant!). That said, it's a godsend.
 
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