Club 80-90 Forums

Does anyone know if it's possible to replace the CV joints on the T25 Driveshafts with those from a Passat/A4 DHL gearbox? I'm not sure if the splines on the end of the shafts are the same size.

I'm doing a conversion and have the old cut-off CV's from the new gearbox and they are in good condition. Rather than fitting driveshaft adapters I would like to use the larger and stronger CV/flanges from the Passat.

Cheers, Dave.

You need the inner cvs from the early t4 90-94 with 32 inner splines. You will also find that the shafts are too short as new diff is narrower by the width of one old cv joint.

MGP wrote:You need the inner cvs from the early t4 90-94 with 32 inner splines. You will also find that the shafts are too short as new diff is narrower by the width of one old cv joint.

So a pair of T4 90-94 CV's will bolt up to the box if a couple of plain spacers are used?

I have the original CV's that came with the gearbox, I could in theory just hack them down with a grinder and clean them up to use the original flanges as spacers. I presume it's very unlikely that these CV's will have 32 splines on the inner part of the joint.

Dave.

Put the spacers on the outside otherwise the shafts will hit the top of the trailing arm. If yours is lowered you may get away with it.

It's not lowered so I'd have to go with putting them at the outsides.

If I was to cut an old CV in half would that work as a spacer? my local machine shop could accurately cut it no bother. Alternatively I was thinking of making up a couple of spacers from 100mm steel stock such as this

http://www.ebay.co.uk/itm/301225270935? ... EBIDX%3AIT

Can you recall if the outer CV's need a Recess into the mating flange? The inner ones need 22mm from the flange to the centre of the cup.

Dave.

On mine when i bolted the box up to the engine it wanted to sit in a position where the n/s shaft bolted up and the o/s wanted a spacer, I did try pushing the box over but it was straining the engine mounts.
For the spacer i just used the outer part of the removed cv with longer bolts

Just out of interest, did you lower your engine in the cradle/gearbox mount or leave it as stock?

Dave.

Lowered it by 40mm using spacers at the front and redrilling the mount bars at the back.

Spot on.

Next question, how did you go about shaving down the 15mm off the bell-housing? I'm having great difficulty getting the main input shaft bearing out as it requires a specific VAG tool VAG1582/2, I need the box stripped so it will fit onto the bed of the milling machine.

Cheers, Dave.

Can't help with that im afraid I did my conversion a long while before an adaptor was available so my bell housing is cut and welded.

No bother, I was thinking of doing that myself, how easy was it to keep the input shaft aligned when you came to reattach the front of the bell housing?

Cheers, Dave.

Easy just made a jig out of an old clutch plate that would bolt to the bell housing, hardest part was getting the correct orientation of the box.

I would consider doing this too but would need someone in the northeast who can weld alloy

I think if I was to do this, I would clamp the input shaft and bolt it to the face of the bellhousing, then cut and rotate the bellhousing round this, then re-weld at the correct position. It could almost be done in one operation i.e., mount, cut, rotate gearbox on its own input shaft, weld.

I have a large flat (8" diameter) thrust bearing that I could mount and rotate the whole gearbox while applying an angle grinder (on some sort of rotating mount) to it. Looking to buy a 9" alloy cutting disk.

Supposed to be buying an adapter plate from Tim at Ultimate Engineering but I get the impression he's mega busy and might not be able to sort it out in the time frame I require.

Dave.

Alloy wire in a mig works ok.

Been trying to find those CV's all over the place, not having any luck so far.

Can anyone provide a part number for them? Just to confirm, from what I can gather they are 130mm diameter with 32 inner splines apparently.

Cheers, Dave.