GKN Differential

[Z5Roadster]

95 Chimaera with GKN Diff, think thats right it has cooling fins on the back casing. I'm looking to change the oil but is the filler plug at the back above the rear exhaust mounting? If it is do I need to drop the rear end of the exhaust or does the underbody section of exhaust need to be removed completely. The bible seems a bit grey in this area. It has crossed my mind to cut a 1" dia hole in the bottom front section of the boot and seal it with a rubber blanking plug but as yet not checked that one out.

[The AJP Griff]

Managed to get at mine using a spanner on a drain plug key.

[Z5Roadster]

I've got the back-end up on axel stands, above the exhaust mounting is the rear cross member of the chassis, the plug is above all this, it all looks very tight.

[Red Cabbage]

There appears to be some slight variations of the GKN diff. Mine has a drain plug on the bottom and a filling plug on the offside. Both can be accessed (I use the term loosely) without taking the exhaust off.

[That Daddy]

Red Cabbage said:

There appears to be some slight variations of the GKN diff. Mine has a drain plug on the bottom and a filling plug on the offside. Both can be accessed (I use the term loosely) without taking the exhaust off.

supposed to have more oil capacity so i am told, your one that is i have seen three 95 Chims and one 96 Griff with the rear filler,but i had a 94 Chim on the ramp recently with the larger cover fitted all cars fitted with GKN units.

[Z5Roadster]

Red Cabbage
I was told that it was quite easy, just take the offside rear wheel off and your there, he must have had the same rear casting as yours , thanks

Edited by Z5Roadster on Thursday 23 October 21:59

[That Daddy]

Z5Roadster said:

I was told that it was quite easy, just take the offside rear wheel off and your there, he must have had the same rear casting as yours , thanks

Thats why you will find mole grip marks on the filler plug on the cars with the rear filling diffs(lazy bast*rds)you can wiggle a short extension on a ratchet to get to the filler plug with your hands shoved thru the chassis tubes(fiddly though)coming in from the nearside,its the getting the oil in thats the pig one thing i have noticed with my spare stripped on the bench is that you can only get about 70% of the total capacity of the old oil out when draining,not ony is the drain plug in the wrong position but the drain threaded boss is raised on the inside meaning that some of the old dregs of oil stay put behind the pinion bearings housings still could be worse could be a Ford with no drainplug,oil lasts for differentials lifespan according to Fords litrature

Edited by That Daddy on Thursday 23 October 22:08

[Z5Roadster]

I have pipegrip teeth marks on mine, you have had quite a few of these to do then! I filled my gearbox by running 16mm bore tube up to the bulkhead with a copper elbow going into the box. Do you think the idea of the 1" hole is possible? Thanks for That Daddy

Edited by Z5Roadster on Thursday 23 October 22:16

[That Daddy]

Z5Roadster said:

I have pipegrip teeth marks on mine, you have had quite a few of these to do then! I filled my gearbox by running 16mm bore tube up to the bulkhead with a copper elbow going into the box. Do you think the idea of the 1" hole is possible? Thanks for The Daddy

We are busy on here tonight i cant see why a hole with a bung would be a bad idea Roadster(seems like a good one)all the GKN units i have seen have had Gripmarks one is my own and the other three i maintain(the other one is me bruvs)all had dealer history at some point maybe the Grips was a special tool used by them

[Red Cabbage]

That Daddy said:

Red Cabbage said:

There appears to be some slight variations of the GKN diff. Mine has a drain plug on the bottom and a filling plug on the offside. Both can be accessed (I use the term loosely) without taking the exhaust off.

supposed to have more oil capacity so i am told, your one that is i have seen three 95 Chims and one 96 Griff with the rear filler,but i had a 94 Chim on the ramp recently with the larger cover fitted all cars fitted with GKN units.

Which has the larger capacity my side filler or Roadsters rear filler?

[That Daddy]

Red Cabbage said:

That Daddy said:

Red Cabbage said:

There appears to be some slight variations of the GKN diff. Mine has a drain plug on the bottom and a filling plug on the offside. Both can be accessed (I use the term loosely) without taking the exhaust off.

supposed to have more oil capacity so i am told, your one that is i have seen three 95 Chims and one 96 Griff with the rear filler,but i had a 94 Chim on the ramp recently with the larger cover fitted all cars fitted with GKN units.

Which has the larger capacity my side filler or Roadsters rear filler?

Side filler as the bigger capacity

[Red Cabbage]

That Daddy said:

Red Cabbage said:

That Daddy said:

Red Cabbage said:

There appears to be some slight variations of the GKN diff. Mine has a drain plug on the bottom and a filling plug on the offside. Both can be accessed (I use the term loosely) without taking the exhaust off.

supposed to have more oil capacity so i am told, your one that is i have seen three 95 Chims and one 96 Griff with the rear filler,but i had a 94 Chim on the ramp recently with the larger cover fitted all cars fitted with GKN units.

Which has the larger capacity my side filler or Roadsters rear filler?

Side filler has the bigger capacity

Thanks I'll remember that when I take it out this winter.

Edited by Red Cabbage on Thursday 23 October 22:53

[Z5Roadster]

That Daddy said:

supposed to have more oil capacity.

Should the filler be used as an oil level, or fill with the recommended quantity

[spend]

Mine takes 2.5l, quickest way to trash the diff is not enough oil and nose bearing runs dry then bingbangbong. Waste a little oil AND check the level afterwards to be sure!

[Z5Roadster]

Tomorrow I will slide underneath, checkout the extra hole method first, if it works it will also get over the filling problem, will post my findings. Thanks Guys

[That Daddy]

spend said:

Mine takes 2.5l, quickest way to trash the diff is not enough oil and nose bearing runs dry then bingbangbong. Waste a little oil AND check the level afterwards to be sure!

always worth checking

Edited by That Daddy on Friday 24th October 08:12

[Z5Roadster]

No No No! Forget the idea of an access hole. Somebodies put an aluminium tank in the boot which goes right to the floor, Don't think we want to drill a hole thru that.

Red Cabbage said:

There appears to be some slight variations of the GKN diff.

This is what I finished up doing. Using a 3/8 drive-1/2 adaptor with 3/8 tee bar (without the bar) I had a go situation, but the exhaust rear mounting plate was in the way of getting the tee bar into the hole.So dropped the anti roll bar from its 4 fixings, off with the rear exhaust mountings so that the pipes rested on the anti roll bar, This gave enough room to unscrew the little blighter. What a pig of a job, dont think the exhaust headers were much worse of a job to do.

[That Daddy]

So good he said it twice

[Z5Roadster]

That Daddy said:

So good he said it twice

Good job somebody's keeping an eye on me