Guide to replacing diff on VY Commodore

[Sickbunny]

Hi guys just wondering if anyone has a guide or tips on how to replace a diff in a vy commodore as i have a 3.7" LSD to replace my standard non LSD 3.07 diff.

I have done a search and cannot seem to find a guide on how to replace them in these cars :(

thanks.
Grant

[Toddler78]

If you are replacing the entire diff including housing, its pretty self explanatry, undo the drive shaft hex bolts, undo the tail shaft bolts, unplug the ABS sensors (2) and undo the 4 bolts holding the diff in. reverse procedure when reinstalling.

if you are using your existing housing and replacing the guts then it is a little bit more indepth then that and requires that you get the crown and pinion gears sitting well with one another, using a paint to check for run out and such. Probably something best left to the experts.

[Sickbunny]

Thanks, its a full bolt in replacement.

[stumps57L]

Get car up on hoist/jack stands
Take catback off - optional
undo tailshaft
undo cv bolts
undo the diff mount bolts either 4 or 2 depending on which bit you undo
undo abs sensors
take off breather hose
undo kframe bolts where diff bolts to kframe - put jack under diff at this point - 4 bolts

remove, replace, and repeat in reverse

Things that make the task faster

allen keys sockets
pnuematic rachet
rattle gun for the big bolts at the back of the diff
rattle gun for the star bolts that hold the donut on

[OMR346]

CV's are an 8mm allen key
Diff to cradle bolts are 17mm
Diff mount bolts are 6mm allen key (from memory)(i also have a Harrop cover, so that may be different)
ABS sensors are 6mm allen key (from memory)


Thats what i can remember off hand.

I replaced my broken 3.73:1 KAAZ with a stock 3.07:1 LSD on Sunday. I will be replacing that one with a 4.11:1 Truetrac once i get a chance to get it built. It really isnt that hard. If you have access to a hoist, then you can swap them over in no time. We done it on axle stands so it was harder.

[vassis]

OMR346 your vy manual or auto?

i just put 4.11s in my manual its sweet but i think its a tad too short unless ur on slicks and massive RPM dumps :)

I read an article how to do this a month ago on street commodore forum and i didnt pay too much attention until i was half way through the importance of doing on axle stand and NOT car ramps.... which is all i had at the time... You must let the rear suspension hang so the cradle bolts can be accessed at ease from the top etc.. i fit a torque wrench 1.5 feet long up there with no dramas on the 4 big 17mm bolts. And yes i did go buy some axle stands best money spent as i may of hurt myself or my baby if i had of kept going. Might sound dumb but if you havnt had to do this before you might not fully understand the commodores 3 link system until you tinker with it yourself.