The AUSubaru.com.au Forums

Hi guys, I have been looking over the threads concerning welding the diff in L series subies, and everyone mentions removing the right rear shaft, and making some alteration to it, such as removing 5mm or so.

I have searched, but can't find any info on what it is that should be done to the shaft to make it easier to insert/remove for going offroad.

Does anyone have a pictorial or good tutorial on how to do this? I am keen to get the diff welded up nice and tight, but would like to know how to make the shaft instertion/removal as quick and easy as possible.

Cheers,

Crundle

while the diff is out shave 5mm off that stub axle on the drivers side

dave

Forgive my lack of mechanical knowledge, but you mean 5mm off the length of the stub axle?

Crundle

Edit: now knowing it is called a stub axle, I found this link

http://www.ausubaru.com.au/showthread.p ... =stub+axle

yeah mate or you could shave some length off the cv- just dont cut off past the locating hole and you should be right.

its dead easy to just jack up the wheel till its off the ground to chuck in the shaft then

If you have longer rear shockers just jacking the rear right up is enough to pull the shaft. I didn't need to cut any off the stub.
It is a good thing to note the right side is always easier then the left. The diff must sit slightly off to the left.

yeh i also am a bit confused about the welded diff is it if the diff is welded is in constant 4x4 even if the gearbox is in 2x2 in this the reason for the shaft removal i dont think i will ever need to put my car in 4x4 while on the tarmac info would be awsome:???: cheers

sorta. if you leave the shafts in - even in 2wd it will bind up and chirp around corners- not very comforatable

When in 2wd all a Subaru does is disengage a gear in the gearbox which powers the rear. All the driveline in the rear still spins. The driveshafts, diff, propshaft, all of it. But because its no longer connected to the front it won't bind. Now when you go around a corner the wheels move at different speeds. Thats why cars use differentials. When you weld a diff it no longer can move at different speed and then the two rear wheels will have to slip while turning. Take out one of the driveshafts (not the propshaft/tailshaft what ever you want to call it) and the rear wheels can turn at different speeds again because they aren't locked together. If you run in "4WD" with one of the shafts out it can make for some interesting driving, and its best not to.
When you stick the the shaft back in and lock it in 4wd for offroad you won't get the problem of lifting two opersite wheels and not going anywhere as both rear wheels always need to turn with each other with a welded rear diff.
Its the rear diff thats being welded. As PT Subaru's don't have a centre diff so you can still put it in 2wd and drive the streets normally. I know a few people who don't bother with taking a shaft out and have no to minimal problems. Just some cherps.

thanks guys i uderstand the concept know which end of the drive shaft do you take the 5mm off the end goes to the diff or the end that goes to the wheel keen to get my diff locked up

or... just to make things confusing for you....

chop 5mm of the stub axles, and the diff stubbs, and on both sides !

makes life soo easy to take shafts in and out

and something else for people to cringe at, just put a cable tie or 2 through the roll pin hole (i havent had any issues yet)

yeah, cable ties work fine.
No chopping of the drive shaft, only the stubs. Just the diff side, but I guess you could do both.

El_Freddo wrote:

Shave 7mm off these buggers, jack up the RHS wheel and remove the shaft for on road driving.

As for actually welding the diff, the images above with the bolts is over kill but will do the job - really any contact point of the spider gears needs to be welded, so this makes each gear welded together where they mesh, and also weld across the top of each gear so it's welded to the housing. This will ensure they don't move.

Also a good idea to keep things cool if you don't remove the bearings off the sides.

You need to remove the diff output stubs to get the centre out, but you can weld it in place if you're careful.

Cheers

Bennie

Found this very useful!! cheers Bennie!

Also I ended up shaving 5-7mm off the wheel hub end.. Not sure if already shaving 7mm off diff stub helped but not is super easy to take the rear axle out. Literally 60sec if you have a decent jack.. And then chuck a couple zip ties in and your suby just got a whOle lot better