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Compressing length of half shafts
bi22le - 11/1/18 at 04:35 PM

I recently fitted a 7.5" diff to the striker, replacing the 7".

Measurements suggest that they are the same width but when i fit the shafts and bolt up the hubs the UJs are compressed.

It was like this before and didn't show any problems but I now feel that I may be compressing them even more.

Is there any issues with having to push the hubs onto the uprights, therefore compressing the UJ?

These are push in shafts and they are fully seated in the diff before I have to push and bolt the hubs on.

nick205 - 11/1/18 at 05:27 PM

From memory of dismantling Sierra driveshafts the joint each end is spring loaded. Whilst that must allow some compression I'd have thought it must be wrong to run them overly compressed for long. Joint failure through wear would seem inevitable.

Dismantled joint for reference...

[Edited on 11/1/18 by nick205]

40inches - 11/1/18 at 06:20 PM

When I last fitted my drive shafts, the hub was out of the upright by 30-40mm this was compressed when the hub was tightened up.
With the drive shafts horizontal I could move the shaft back and forth by a small amount, this was against spring pressure from the joints, around 20mm I think.

madteg - 12/1/18 at 02:16 PM

I shortened my shafts by moving the circlip grooves back 5mm on each end. Cut new groves with grinder in a lathe with 1mm cutting disc, then cut 7 mm of each end, so each now 14mm shorter with no compromise to the strength. Hope this helps