Has anyone ever looked into narrowing an F series diff

[slydar]

specifically a tarago type.

shortening the axles once done doesnt seem too tricky. but the actual shortening of the housing?

ive got a pretty good idea of how to do it but if anyone can point me in the direction of some write ups, just for a few extra pointers/confidence.

[Sam-Q]

with the work I have seen you do I am sure you could do it easy. I will take a picture of the tool I made to do a skyline housing

[johl]

If you need a test diff let me know d. This would solve my problems if you could take 20mm off as I have heard the axels have an extra 20mm off teeth that sit outside the centre?

[slydar]

cheers. and yeah id like to see it.

[ke_70]

interested in this as i'd like to do mine as well.

[slydar]

Johl, yeah there is always a bit of extra spline. just really busy ATM but i definately plan to get one and give it a go. in theory it shouldnt be super hard. but with things moving with heat etc.

[Sam-Q]

here you go as promised:

http://www.ae86drivingclub.com.au/dcimages/2/5/2/241040.jpg

just a big chunk of angle with flats welded on. The flat sections allow the twin C-clamps on either side to be done up super tight. It's pictured upside down to how I sit it with half of either end of the chopped diff tube sitting in the V shape to hold it straight.

With a bevel on the housing I do selective welds on both far outer edges equally before removing the clamps to grind the welds flush and rotate this support 90 degrees to weld it top to bottom. I use selective limited welding on opposing sides to stop it warping. End result was oil tight and dead straight. I also did the sneaky move of making the join end up in the middle of where the control arm mount would be welded on for extra strength.

[slydar]

had to read that twice but now ive got it. seems like a nice simple way to do it.

what i have seen before/planned to do was cut the weld of the wheel bearing "holder" on the end of the axle tube. shorten it there and weld it back on.

someone suggested this might be the way to go as any mistake/misalignment you make is not amplified like when do it closer to the center.

the hard part doing it that way though is not so much getting it square, but getting it concentric. not too sure how tight a fit that bearing housing is. luckily there are some pretty cheap wreckers around so if i botch it its not the end of the world.

[kaibeecee]

worse comes to worse just get the bearing seat reamed/faced before re-fitting, i dont think it would warp that bad

[slydar]

yeah not to worried about that. more just getting it aligned with the axle center line.

[LittleRedSpirit]

You can slip (hammer) or interference fit a collar around the inside of the tube that you cut, to help locate the tubes perfectly in line. Takes more heat then too, as there is more metal to absorb it.