Diff bolt/stud removal and replacement

[Veryan]

Hi All,

I need to replace the bolts/studs that hold the diff on as several were cross threaded in the process of removing the nuts. The type fitted have a hexagonal head and are wired in:




I spoke with some guys over east on the phone and they think that they should unscrew - can anyone confirm this? How exactly do they come out? I briefly tried with a spanner, but nearly broke it.

The replacement parts I have are studs with splines - will these fit, or can I get away with using 3/8" UNF bolts? This is what the thread is at present - is this ok or is there a flaw in my plan.

All help greatly appreciated,

James

[isuzurover]

The later type press in and out, as mentioned. I can't recall seeing ones like yours - but I upgraded to SIII/Stage 1 axles a long time ago. If yours don't knock out with fairly gentle tapping from a hammer, then they must be threaded in.

Check the diameter of the splined section on the new bolts. If it is larger than the threads on the old bolts, then you can just cut them off and drill them out if they won't unscrew easily.

p.s. - a bit of heat may help them unscrew.

[chazza]

My S1 has the wired bolts like yours and I am fairly certain that I tightened a loose one by using a spanner.

What about buying a die-nut, or a thread file to repair the threads, unless they have been totally stripped? Even winding a die on by hand might work, if they are not too badly damaged,

Cheers Charlie

[Veryan]

I have a die nut and managed to save the front diff bolts, but the rear are a little worse for ware.....i tried the one in the bottom of the photo and it does not show it very well but its almost a smooth stud....

Will give it a bash tomo night...only just got home. too tired.

[Veryan]

So it turns out that if you have wired hexagonal bolts then they are BSF and if they are studs they should be UNF - should have paid more attention to the parts manual.....arrgghhh!

[Aaron IIA]

So it turns out that if you have wired hexagonal bolts then they are BSF and if they are studs they should be UNF - should have paid more attention to the parts manual.....arrgghhh!

That would make sense, as you would have had to use your Whitworth spanners to get the differential housing off in the first place.

Aaron.