Rear differential - checks

[swood1]

Hi all,

Just been stripping my rear suspension down.  I haven't yet removed the drive shafts, my intention is to check and replace all perishable items.  Can anyone advise on the steps I should be taking for checking my rear differential?  The intention is to strip the centre axle and replace the sleeved rubber bush.  I would also like to replace the UJ gaiter so was thinking of stripping the drive shafts and the drive shaft tubes.

Any advice/guidance welcome.

Steve

[Benz Dr.]

Make sure you mark the position of everything on your drive shaft if you take it apart. Drive shafts are carefully balanced and any disturbance or misalignment may upset the entire assembly.

Whatever you do, DON"T remove the pinion bearings. Any movement of the crown and pinion gears and you might as well look for another axle. It can be set up but not by mere mortals and it would likely cost a lot to do.

[swood1]

Ah sorry when I said drive shaft I meant axle shafts, the shafts that connect to the wheels.  My main drive shaft has already been removed and I marked that with a dot punch.  To be honest the differential itself feels tight, I was going to remove the Pinion coupling flange using a modified socket as it looks like I need to take this off so I can replace the centre axle sleeved rubber bush etc.  I also wanted to remove the axle shafts so I could replace the bellow with a new one piece one.  It would have been nice if I could have got into the differential to check the play in the crown wheel with a DTI but I am not sure this is achievable without a full teardown.

[Benz Dr.]

You will need to remove the flange on the pinion to get everything apart. Carefully mark the pinion nut before you start tear down so you can tighten the nut back to the same spot.

[ja17]

This is quite a project for the first-timer.  I have made a lot of special tools over the years to help make this project easier. It becomes a lot easier after doing several. Ask a lot of questions and we will try to save you from making the usual mistakes.

[swood1]

Thanks all,

There is always a first time for everything and I am a qualified watch and clock repairer and also work as a Freelance Automotive Validation engineer. But I originally served my time as a Toolmaker before the industry all went abroad. so happy with new mechanical challenges.  I also have my own workshop.. currently making a tool this week to allow me to remove the nut holding the flange in place, I have read on the forum but I dont want to destroy a perfectly good socket   

I will mark the parts, and get some photos of the assembly so the forum can feedback.

Also, I have been struggling to release the pistons in the rear brake calipers.... the front ones I freed using a little heat. 


Steve

[DaveB]

Removing pistons - I've seen brake rebuilders do it, they pump a fluid into the caliper to force the piston out.

[swood1]

Hi Dave,

I have been thinking similar if soaking them in oil doesnt work. 

Failing all this it's new rear calipers for me...

Steve

[450sl]

better to use a grease gun to pump out pistons , less messy.......:just fit a grease nipple into the brakeline hole and pump away..

[Atazman]

I use compressed air.  No fuss; no muss.

[swood1]

I have tried compressed air, no joy...

[Bonnyboy]

Grease is a much safer approach in my opinion to ease out the piston.  Major chance of squishing digits with air.  I got a hint to put a piece of wood slightly smaller than the distance the piston could travel if it lets go in the caliper so that the piston doesn't fly out and damage something.  Then clean it all out.