Welding on diff housing

[Sausager]

I need to do some welding on my diff housing, but I don’t want it to bed and bow. What is the best way to get around this? Preheat the area I am welding? Tack the housing to the bench? Brace it before welding?

I need to fully weld the box to the housing in the notch that I have cut out in the housing



Cheers

[De-Ranged]

I've welded more diff shaves than I can remember lol after all them I've come to the conclusion after trying alsorts of different ways the most accurate is to tension the housing in the opposite direction so when I weld the weld shrinkage pulls it straight again.....I have a jig I've built to do this
Sorry I've had a look through my photobucket and can't find a pic of the jig (plenty of diffs in it but non that show the jig...) I've used a piece of I beam that has a couple of chains at the ends that I can tension to pull the diff.... for what its worth I pull a hilux diff about 10mm on each leg prior to welding and this is usually within 1/2 a degree of true

if you do get some pull from the weld that bends the housing you can counter this by heating a 50c sized area on the opposite side to cherry red with a gas axe then let it air cool all the way to room temp and measure again each one of these will pull the axle around half a degree

[BlakeNZ]

Reece, i have both texted and "Pm"d you with regards to the cost of a diff shave, but no reply from you. Lost messages, or just not keen?

[De-Ranged]

Sorry Blake I thought I'd PM'd you back, I'm no longer doing any mod work commercially, lol I don't even get enough time in the shed to do much for myself... I'm happy to help with advice but I just don't have the time
My suggestion would be Toms Offroad or Howe

[tomsoffroad]

Cheers for the props Reece

I too use a chuck of I beam (well actually 2 pieces of 200mm channel welded back to back) with chains and a bottle jack. Cheap jig to build, works mint.

[Sausager]

OK, so prebending the housing is the best way? Holding it rigid when doing the welding isn't enough? I'm sure I could work something out. Thanks for your help guys!

Talking about diff shaves - what do you guys do for a drain plug? Just remove it altogether?

[Checkerhead]

I know some people remove one of the lower studs (that hold the diff head in) and replace it with a bolt so that this can work as a drain.

Personally I think I'd want something bigger than that.

[LOLYF]

I had my diff shaved by Jono at JRC, he relocated the drain plug off to the side.

[Sausager]

That's an idea, yeah.

If I was to do a diff shave at the same time as welding that box in, which way would I prebend the housing? The shave is obviously welding on the bottom of the housing and the box is on the top. Weld one, let it cool, flip the housing over, pull the opposite way and then weld the other?

[Madaz]

Ive always done the shave with a diffhead bolted in and made the filler plate a exact fit, havnt had to many issues sofar

[NOBDY]

x2 on Jono's diff shaves

[De-Ranged]

Ive always done the shave with a diffhead bolted in and made the filler plate a exact fit, havnt had to many issues sofar

I also use an old diff head that I cut down and can fit a true'ing bar through it so I can see how much I have moved it when I pre tension and how much I have to correct the diff to line it up again.... all that said I personally think they can stand a fair bit of miss alignment, the reason I go to the level I do is if your charging for service you do it properly and I can say to the client it is true and mean it lol

Oh also I do way more than one plate when I shave lol, I shave the axle angling out to the axle tubes I then shave the diff pan about 1/3rd of the way up


That was a tame rover diff.... I've done more radical lol

As for the drain I swop a bolt for the lowest stud.... the way I see it, the drain is only there for checking for water if you want to change the oil your also going to want to check the diff out so your pulling the head why compromise all that hard work by having a drain hanging down or you move it up and too one side so it never drains the sediment and metal filings.....

[LOLYF]

Why would I want to pull my front diff out every time I change the oil?
If excess sediment is found while doing an oil change ( which you may not see draining through a 6 mm hole) then I will go to all the effort of removing the front diff, in the mean time I'll stick to keeping my magnetic drain plug doing its job!

[Clint]

If you truss the top & shave the bottom it all evens out according to my wheel alignment report

Good advice from deranged though - if you want to be fussy I'd do each bit separately, prestressing it to suit.

Cheers
Clint