Hey, Team.
Apologies if the info is somewhere on the forum, I have searched and searched...
I am rebuilding the 14HU differential in my 2000 4.0 XKR. I am a reasonably competent home-mechanic (rebuilt my own motors, built a couple of kit cars from scratch, etc, etc) and am happy dismantling and reassembling g the diff with new bearings, seals etc.
What I can not find are the preload figures for setting the conical bearing tension.
In simple terms, you reassemble the diff, torque everything up to factory spec, then hook a ‘fish-scale’ onto the input flange, pull the scale and read the ‘force’ figure just before the flange rotates. Too little and the shim thickness inside the diff needs to be reduced to tighten everything up. Too high a preload reading and shims need too be added too loosen the pressure on the conical pinions bearings.

Does anyone here have access to the preload readings for tensioning the pinion (input shaft) bearings in this diff?

Thanking you in advance.
Gazza.

 

 

I think you would be better off using a beam or dial lb.in torque wrench. I can't help with specifics for the 14hu but with new bearings l would think you want something around 15-20 lb in to rotate the pinion. Disregard breakaway reading and only note torque needed to keep it rotating.

 

Good thinking, Baxtor. That makes perfect sense. Many thanks.

I'm still looking for any specific internal working drawings of the diff and/or a list of seal and bearing part numbers. Here's what I have so far:

Pinion Seal:
JLM20326
104702
52 85 10

Pinion Inner Bearing:
JLM20335

Pinion Outer Bearing:
JLM20334, now:
NJF-215-312-AA

Carrier Bearings:
JLM-20336 x2

Output Shaft Bearings:
???…x2

 

...more questions: :

The previous owner had replaced the pinion oil seal in-situ as it was leaking. When I got the car the diff was making a whining whah-whah noise that was directly related to wheel speed. The diff oil was down to 1.3 litres (from memory) and takes 1.9 litres (again from my (ageing, gin-addled) memory).

When I dismantled the pinion tail there was no 'Ryton Ring' between the pinion oil seal and the pinion drive flange. The Ryton Ring does not appear in the exploded diagram above but is specifically mentioned in the TB and the Workshop Manual.

Q1: Ryton Ring. Needed? Obviously yes, but I had to ask.
Q2: Does anyone have a part number for this item?
Q3: Function of the Ryton Ring? I'm picking it is used as a support for the pinion oil seal casing?

Thanks in advance.
8^)-
Gazza.

 

SNG sells a replacement output shaft bearing kit with a spacer, the actual bearing is custom size and unavailable

 

l fitted those to my diff a few years ago and made note that the spacer needs modifying and should be fitted on the output shaft before the bearing, not behind.
This is due to the mismatch between the bearing chamfer and the radius at root of the shaft flange. The original jag bearing has a chamfer to suit.

 

Thanks, Team. Pulled more parts off the diff this morning. Stay tuned! Gazza.