Re-casing a diff? - Drifting forum

royal · 17-09-2008, 17:48

I asked a similar question before but is there any reason not to re-case a diff yourself? I know people have talked about getting someone to set it up properly (whatever that involves!), but if I've got a 1.5 way and a 2way already on cars and want to swap the actual diff unit around but keep the cases. Is there anything I need to do other than take apart a few bolts and swap the units over? do I need to replace anything?

Incidently the reason I can't just swap the diffs and their casings is because I've got a different input ratio (not sure what you call the first cog off the prop?) on my casing so want to keep it. A mate has a 2 way and wants to swap it for my 1.5way.

orange_beastie · 17-09-2008, 17:58

yer thats easyily done take ur diff off the car take the bolts out the rear casing,
then remove the 4 bolts that hold the bearings in the remove the bolts from the main gear then swap them over just make shure the halfshafts fit as they may be differnent?

royal · 17-09-2008, 18:01

Cool, ta muchly. Wasn't sure if any of the setup stuff was involved.

orange_beastie · 17-09-2008, 18:03

didnt know you had to set them up? done mine the other day had it complety striped and cleaned then welded up the standard diff n put it back togetther and it works fine.
so simply swapping them over shouldnt affect anything.

royal · 17-09-2008, 18:20

These arn't standard diffs mate, they are 1.5 and 2way clutch diffs. I think you can just throw them in but ideally should be set up by a man in a white coat. There's a bunch of adjustment you can do; pre-load and stuff which effects the way they lock up. I'm 99% certain thats all internal to the unit anyhow, but wanted to check as I've never done one before.

orange_beastie · 17-09-2008, 18:24

yer but what i mean is if your cars are similar then you shouldnt need to set them up. should simply be a straight swap?

20vWill · 17-09-2008, 18:28

Dave - you should be OK for what you are doing, just make sure everything is meticulously clean, shims go back in the right order, all the torques are right, Loctite 270 ish grade on the ring bolts, lightly file the mounting faces of the ring gear and diff before mounting.

It's worth checking pinion preload (and adding a little more) while the centre is out, also gear contact pattern and backlash should be checked when assembled, and shim added to both sides to increase carrier preload. This builds a stronger assembly.

Though if you want one built to last you need expertise and a few special tools.

royal · 17-09-2008, 18:53

Thanks Will. I was going to Pm you but couldn't remember the right username! If you don't mind I may stick a few questions up as i do it? I've got a spare 1.5/2 way which I'll practice on first as I don't want to change my mates unless I'm confident!

PhatBob · 17-09-2008, 20:51

Go here:
Randy's Ring & Pinion. How-To Articles and Technical Instructions.
Read all that you can.

royal · 17-09-2008, 21:28

Great link, ta muchly

17-09-2008, 17:48	#1 (permalink)
royal S1- F.T break! Join Date: Nov 2005 Posts: 4,819	Re-casing a diff? I asked a similar question before but is there any reason not to re-case a diff yourself? I know people have talked about getting someone to set it up properly (whatever that involves!), but if I've got a 1.5 way and a 2way already on cars and want to swap the actual diff unit around but keep the cases. Is there anything I need to do other than take apart a few bolts and swap the units over? do I need to replace anything? Incidently the reason I can't just swap the diffs and their casings is because I've got a different input ratio (not sure what you call the first cog off the prop?) on my casing so want to keep it. A mate has a 2 way and wants to swap it for my 1.5way.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

17-09-2008, 17:58	#2 (permalink)
orange_beastie touge runner Join Date: Aug 2008 Location: kings lynn Posts: 213	yer thats easyily done take ur diff off the car take the bolts out the rear casing, then remove the 4 bolts that hold the bearings in the remove the bolts from the main gear then swap them over just make shure the halfshafts fit as they may be differnent?

17-09-2008, 18:01	#3 (permalink)
royal S1- F.T break! Join Date: Nov 2005 Posts: 4,819	Cool, ta muchly. Wasn't sure if any of the setup stuff was involved.

17-09-2008, 18:03	#4 (permalink)
orange_beastie touge runner Join Date: Aug 2008 Location: kings lynn Posts: 213	didnt know you had to set them up? done mine the other day had it complety striped and cleaned then welded up the standard diff n put it back togetther and it works fine. so simply swapping them over shouldnt affect anything.

17-09-2008, 18:20	#5 (permalink)
royal S1- F.T break! Join Date: Nov 2005 Posts: 4,819	These arn't standard diffs mate, they are 1.5 and 2way clutch diffs. I think you can just throw them in but ideally should be set up by a man in a white coat. There's a bunch of adjustment you can do; pre-load and stuff which effects the way they lock up. I'm 99% certain thats all internal to the unit anyhow, but wanted to check as I've never done one before.

17-09-2008, 18:24	#6 (permalink)
orange_beastie touge runner Join Date: Aug 2008 Location: kings lynn Posts: 213	yer but what i mean is if your cars are similar then you shouldnt need to set them up. should simply be a straight swap?

17-09-2008, 18:28	#7 (permalink)
20vWill ...... Join Date: Jul 2004 Location: Doon Sooth Posts: 3,856	Dave - you should be OK for what you are doing, just make sure everything is meticulously clean, shims go back in the right order, all the torques are right, Loctite 270 ish grade on the ring bolts, lightly file the mounting faces of the ring gear and diff before mounting. It's worth checking pinion preload (and adding a little more) while the centre is out, also gear contact pattern and backlash should be checked when assembled, and shim added to both sides to increase carrier preload. This builds a stronger assembly. Though if you want one built to last you need expertise and a few special tools.

17-09-2008, 18:53	#8 (permalink)
royal S1- F.T break! Join Date: Nov 2005 Posts: 4,819	Thanks Will. I was going to Pm you but couldn't remember the right username! If you don't mind I may stick a few questions up as i do it? I've got a spare 1.5/2 way which I'll practice on first as I don't want to change my mates unless I'm confident!

17-09-2008, 20:51	#9 (permalink)
PhatBob Ken Block??? Join Date: Aug 2004 Location: Newmarket Posts: 1,775	Go here: Randy's Ring & Pinion. How-To Articles and Technical Instructions. Read all that you can.

17-09-2008, 21:28	#10 (permalink)
royal S1- F.T break! Join Date: Nov 2005 Posts: 4,819	Great link, ta muchly