switching diffs

Discuss mechanical problems here.
dudload
Minor Fan
Posts: 306
Joined: Tue Sep 01, 2015 10:37 am
MMOC Member: Yes

switching diffs

Postby dudload » Thu May 16, 2019 4:07 pm

afternoon all!

so I've recently come into possession of a 3.9 diff, and was wondering if anyone has any tips / guide on how best to switch out the old 4.2 for the new one? any pitfalls, things to know?

Thanks!

Online
philthehill
Minor Maniac
Posts: 6891
Joined: Thu Jul 19, 2012 12:05 pm
MMOC Member: Yes

Re: switching diffs

Postby philthehill » Thu May 16, 2019 7:05 pm

A relatively easy job to do with no pitfalls that I know of.

Has the axle case got the axle filler plug in the rear face of the banjo?


liammonty
Minor Addict
Posts: 898
Joined: Mon Apr 23, 2007 2:32 pm
MMOC Member: No

Re: switching diffs

Postby liammonty » Thu May 16, 2019 8:41 pm

Make sure that you put the halfshafts back in on the same side you took them out of, or you'll end up with them breaking!

dudload
Minor Fan
Posts: 306
Joined: Tue Sep 01, 2015 10:37 am
MMOC Member: Yes

Re: switching diffs

Postby dudload » Fri May 17, 2019 9:05 am

yup - filler is on the back of the axle, so will still have a place to top up :D

anything else I could check whilst I've got it off? checking replacing UJs? Which reminds me - I need to mark the prop shaft with chalk to indicate which side was up don't I?

oliver90owner
Minor Addict
Posts: 832
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: switching diffs

Postby oliver90owner » Fri May 17, 2019 1:18 pm

dudload wrote:
Fri May 17, 2019 9:05 am

anything else I could check whilst I've got it off? checking replacing UJs? Which reminds me - I need to mark the prop shaft with chalk to indicate which side was up don't I?
It will be down one half turn later!

lukedauvergne
Minor Fan
Posts: 101
Joined: Tue Feb 10, 2009 8:48 pm
MMOC Member: No

Re: switching diffs

Postby lukedauvergne » Fri May 17, 2019 4:42 pm

Nice easy job using basic tools make sure to tighten the housing up evenly and for the little amount they cost i would get a spare gasket I learned the hard way that tightening the housing unevenly ended braking it and over tightening the bolts lead to a broken gasket nothing worst than waiting another couple days for parts

Online
philthehill
Minor Maniac
Posts: 6891
Joined: Thu Jul 19, 2012 12:05 pm
MMOC Member: Yes

Re: switching diffs

Postby philthehill » Fri May 17, 2019 4:59 pm

You normally mark the diff flange and the propshaft flange adjacent to one another before removal but as the diff will be new in relation to the propshaft there is little point in marking either.

If the balance does not feel right after fitting the propshaft it can always be turned on the diff flange by 180 degrees to see if the balance is better and/or any vibration reduced.

The diff assy is secured to the axle casing by studs, nuts & spring washers not bolts - mentioned in case someone queries their diff to axle case fixings.

Care should be taken (as stated above) when tightening the nuts.

Fit new diff gasket which has been lightly greased.

Phil



Who is online

Users browsing this forum: No registered users and 9 guests