hj75 rear diff housing options?

[sodafeld1]

What are my options for replacing the bent rear axle/diff housing of my 1988 hj75 troopy? Please excuse my ignorance.

Simply the same width and perch would be ideal.

It would be great if I could upgrade but must admit looking for an easy swap.
Rear disc brakes would be nice.

There are a few mobs who build diff housing upgrades in Oz but only for later model landcruisers. Which is a bummer, not enough market I guess. Are the housings fabricated from typical mild steel?

Is the bj70 same axle housing width as the hj75's? Isn't there a mob in the US. which makes axle housings for the bj70? Shipping would be a killer though.

I would be lucky to get a straight housing off a wreck.

Easiest fabrication from something newer and stronger?

How much would it cost approximately if I got mine straightened? If I removed the diff and brought in the housing. Just could not picture it being as strong as the original. Is it possible to strengthen the existing?

A neighbour is offering a 60 series rear diff and housing, but I would have to modify the perch and it is wider too. Probably shock mounts. Also I would have to change the front diff housing too, as front and back the same width kind of makes sense to me.

 

[pithicus]

You could give the straightening a go yourself with a big bottle jack and some sort of jig to hold it .

Or use both 60 diffs and a spring over axle? [lot's of work and I "think' you still have to cut into the 3rd member housing on the front diff a little bit.]

even something as simple as this would probably work.

 

[sodafeld1]

Interesting vid, but need a few more tools and things. Lathe, proper oxy torch..where to get a nice straight datum rod as such would either be a hunt or a price. I have a short one from an old lathe, but not the length of a whole housing. Maybe solid aluminium rod, but would have to keep heat away from it.
Doable if an easier swap cannot be found.

The axle housing is not all that strong really, the weak point. The actual axles are strong as.

What is the advantage or need for spring over axle if using 60 series housings please? Sorry if a dumb question.
60 series would make everything a bit wider wouldn't it? Is that extra stress on steering or negligible?

 

[pithicus]

I'm not the best person to ask re spring over jobs, but from memory the 60 front diff has to have the perches moved to line up with the 70 springs, and thus cuts into the 3rd member housing. With a spring over, it doesn't cut in to the housing as much. [I think} The rear diff perches have to be moved as well, but it's easier.
I might be wrong, so best wait for others to chime in.

I don't know how crucial it is to heat the axle housing when straightening?

Spring overs look really cool. A lift without doing a lift!!

 

[sodafeld1]

Hmm, I just did a 2inch lift, 500kg constant springs in back so even more height there unladen. More height again with spring overs..already ex fire truck orange..insurance always asks what mods.

anyways, this looks like a good link for straightening; Straightening a rear end housing - https://www.crankshaftcoalition.com/wiki/Straightening_a_rear_end_housing

 

[pithicus]

If it were mine, I would definitely try and do my own straightening. It doesn't need to be 100% perfectly straight.
I wouldn't even use heat, but i'm a bit agricultural lol.
It got bent without heat .

 

[Indestructible 47]

Call your local dealer and ask for the parts department. Ask them for a price for an axle housing for your application. The new ones are a bit over 2k. Otherwise try a wrecking yard. I'm personally not a fan of repairing broken parts, just replace where practical.

 

[sodafeld1]

Yeah man, I hate out sourcing.
Fingers crossed, I am getting a 85 troopy wreck delivered, hopefully that rear housing is good and straight. If not, I have a spare to play around with whilst keeping the daily drive.

Currently, the bent housing must not be much as there is no leaks, no sign of uneven tyre wear (rotate them regularly), runs sweet on the tar, but not truly aligned and probably never will be whilst the rear is out of whack. The rear inner wheel bearing is a pain to cut/grind off. The hub only comes off with coaxing. The good side the hub comes off like in the movies.

Never would have known unless I adjusted toe in from back of rear tyre to front of front tyre with a straight edge. One side dead straight, the bad side 8mm from front of rear tyre to straight edge whilst touching back of rear tyre and back of front tyre.

Don't understand why they made the axles so strong but the housing not so strong..

 

[sodafeld1]

amayama has a new one for $2k + shipping
I'll check the wreck first

 

[sodafeld1]

I would invite anyone to check how straight your axles line up with a 4m straight edge, rear tyre back to front tyre back. Front of front tyre should toe in. Hopefully there is not an unpleasant surprise. A slight pull to my left at some speed, inner wheel bearing stuck to diff housing, bad left rear axle housing.