Broken Diff

[ancullen]

Finally got around to pulling the back plate off the back of my diff after breaking something in it two weeks ago. Got the cover off and discovered I've broken the spider gears. So we're going to see if we can weld it up until I can work out what LSD I want to use and will best suit my purposes (preferably one that will be possible to attach disc brakes to) and then wait until I've got the funds to afford it.

 

Any tips of welding diffs?

[oh what a nissan feeling!]

Welding of diffs is something that is not as easy as it should be, apparently something to do with the hardened gears, or some crap. I have done a few, with both the stick and mig and one lasted a record of 2wks :D maybe a pro job is the go?

 

I don't recomend welding an already broken diff though, it has proved to be very dangerous. A mate of mine who had also broken his spider gears, welded the diff up so that he could get back to his place (a 40 minute drive on the highway), he got about 20 min along with no dramas, then the thing locked up at 100ks, :D , that was the end of that car.

[Rolla__Boy]

I had a locker in my car for almost 5 years, it was good fun, at one point we also welded one of my diffs up with a stick, it lasted a few weeks and then snapped, I managed to drive the car home, we pulled the backing plate off and half of one of the sun gears had snapped, and was floating around in there. So we pulled it out, slapped the cover back on, put the same dirty old oil in...and went back out that night to enjoy more "grass driving events"

 

We have also welded some broken ones and had no problems with them.

 

As for tips, I think it's best done with a mig and get as much heat into it as you can. My mate did his diff in the rolla with the 202 in it, and he chucked all sorts of bits and pieces in there until the centre of the sun gears was just a big ball of metal, which makes it hard to get broken axle splines out, but it's damn strong. The 202 allows the thing to swing donuts in 4th gear from a standing start, and it has been in a drift day. The diff has broken one axle, and has been on the road for months. I thought the 202 would tear the diff to pieces.

[Super Jamie]

yeah, the :) locker lasts forever. you'll break axles before you break the center

 

most people just tack the spider gears together. he makes a full spool out of weld, it looks awesome

[ancullen]

Hmm, will investigate. Thanks again guys.

[SLOTH Snr]

The only way to go is a full weld.

Just tacking is a waste of time

Its all in the preperation and

using the right consumables.

Arc or mig should make no difference.

[coln72]

Old man does mine using an arc welder and stainless rods. Welds the gears together and the gears to the housing as well. Usually get around 3 years out of them before the big bang.......

[ancullen]

Three years should be plenty. Tah muchly.

[Rolla__Boy]

3 Years is awesome. What sort of driving is this with?

 

I do burnouts on all my lockers, I think it tests them well, and I have only had one last years, then the pinion gear snapped almost in half. Welds are still perfect

Edited November 9, 2005 by Rolla__Boy

[cookie]

Welding of diffs is something that is not as easy as it should be, apparently something to do with the hardened gears, or some crap. I have done a few, with both the stick and mig and one lasted a record of 2wks :) maybe a pro job is the go?

 

I don't recomend welding an already broken diff though, it has proved to be very dangerous. A mate of mine who had also broken his spider gears, welded the diff up so that he could get back to his place (a 40 minute drive on the highway), he got about 20 min along with no dramas, then the thing locked up at 100ks, :) , that was the end of that car.

 

second it no joke

[rolla13bt]

i broke the weld on a side gear once, which means only one wheel gets any drive. 5th gear burnouts not a problem. another way of doing this is pulling the pin out and removing the two spider gears ''leave them out'' and then weld the two side gears. i like to grind a shamfer on the gears befor welding, ''lets you get better penno'' then just grind the spline off which ever axle you don't want to spin. makes the car a little floaty under acceleration and deceleration tho. but it'll make your 3 or 4 k look like it's got 50hp instead of 25.

[coln72]

3 Years is awesome. What sort of driving is this with?

 

Competition stuff, mainly motorkhanas and autocrosses and such. Doing them on sealed surfaces puts a fair load on everything driveline. Those who have seen me compete will tell you that I don't hold back.

[ancullen]

i broke the weld on a side gear once, which means only one wheel gets any drive. 5th gear burnouts not a problem. another way of doing this is pulling the pin out and removing the two spider gears ''leave them out'' and then weld the two side gears. i like to grind a shamfer on the gears befor welding, ''lets you get better penno'' then just grind the spline off which ever axle you don't want to spin. makes the car a little floaty under acceleration and deceleration tho. but it'll make your 3 or 4 k look like it's got 50hp instead of 25.

 

Interesting theory EXCEPT I want power to both wheels, and I'm not running a 3K or 4K. I'm running a 4A-GZE, so it's got about 120hp at the wheels. Not going to be doing burnouts, just want it to be able to grip through corners while I am circuit racing it. It only has to last twelve months as I'll stay on the lookout for a proper LSD, of course, the longer the welded diff lasts, the better.

[rolla13bt]

i had a stick locker behind my old 4AGZE and never broke it. as long as you prep it it'll be fine. best way is to pull the crownwheel off, pin spider and side gears out and clean it well with petrol. then pre heat the centre with an oxy or stick it in the oven for a while. doing this will stop the welds from cracking as the centre absorbs the heat from the welds. you will also want to put it back in the oven once you have finished and slowly bring the heat down. this will stop it from cooling down to quickly and stop it from cracking also.

don't put bolts and crap in there, it'll just make you look like a dodgy c**t.

or you could also get the centre filled with aluminium.

[ancullen]

Getting the centre filled with aluminium would cost money, and if I'm going to spend any money it's going to be on an LSD. I'll stick to the cheap way this time, thanks anyway.