Replacing Pinion Flange on rear diff.

[Bohica]

I have found a rear diff from a D1, it has the regular 4 bolt pinion flange. It seems easy enough to remove this and replace it with a factory 3 bolt pinion flange, which will come out of the old diff. Is this easyish or am I missing something? I plan on using a bearing puller to pull the flange out. I guess that the splines are the same on both types.

[discorevy]

You may need a slide hammer to remove the spigot covering the flange bolt, but once that bolt is out, they usually come off with a few gentle taps.

Replace the pinon seal while you're there. Yes, easy job

[AK83]

IIRC there is an M8 thread in the spigot.
Use 3 bolts.

A flat plate of steel of some kind(or angle or whatever you have access too) drill three holes in the steel plate to line up with two on the yolk and one for the spigot. Size dont' matter, as long as you can get them to line up.

2 long-ish bolts in two of the the yolk bolt holes with nuts to hold the plate forward a few cm from the nose of the spigot. So in effect you need two bolts and 4 nuts. 2 nuts hold it at the yolk and 2 nuts at the plate to stop it sliding back.

The idea is that the M8 bolt is wound into the spigot, and if the plate is held forward it pulls the spigot out as you turn it(no nuts on it). Just thread it into the spigot.
I think the spigot has about 50mm of thread.

Those spigots can get stuck in good and firm. I tried the slide hammer on my spare parts D2 and no way it would move. I had to use two angle bars, where only using 1 bent in too much.

On the D1 and D2 where I changed donut and spigots and internal bushes and stuff, they came out more easily just with this 6mm flat bar I used.

[discorevy]

I was in another shop and didn't have my large slide hammer with me, so I used a 42mm? Socket, M8 x 1.25 x 50 odd mm long bolt and penny washers to use as a puller which worked.
Pipe with the same I.D. could also be made to work.

[d2dave]

Can you get the tailshaft from the donor car where you got the diff?

If so, leave the flange and you get rid of that stupid rubber coupling.

[Bohica]

Donor car is a D1, the prop shaft is shorter. So I've been told

[d2dave]

Early D1 and RR Classic shafts are what you use when changing from doughnut to uni.

So if you can get the shaft it will fit.

Did mine 10 years ago and the benefits are worth it, especially if you have ACE.

[James NZ]

Did mine 10 years ago and the benefits are worth it, especially if you have ACE.

Hello Dave, I'm wondering why a uni/uni rear driveshaft makes a difference to ACE?

Cheers, James NZ

[d2dave]

Hello Dave, I'm wondering why a uni/uni rear driveshaft makes a difference to ACE?

Cheers, James NZ

In the picture you will see a part that I have highlighted with a red arrow.

When this part breaks and if you do a bit of off roading it will,
what then happens is the ACE ram drops and the hydraulic hoses rub on the doughnut, wear through and game over.

When you have a standard uni join the hoses do not hit. I had mine break out in the bush on a trip.

All that happened was stabilisers don't function as intended but I still finished the trip and drove home.

I even carry one of the pictured links as a spare now, even though I can still drive with out it.

Another advantage of getting rid of the doughnut is being ease of getting to the nut for the flange.

I had an issue once when in the bush. I noticed oil leaking from the flange seal. Turned out the pinion nut had come loose.

It was an easy fix. Unbolted the tailshaft, tightened the nut and finished the trip.

Try doing that with the doughnut.

195068

[DieselLSE]

I had mine break out in the bush on a trip...

I had an issue once when in the bush...

I'm surprised that you ever leave home Dave.