C4: Gearbox Oil & Front Differential Oil Change
11-28-2011, 03:08 AM
#1
Rennlist Member
Thread Starter
C4: Gearbox Oil & Front Differential Oil Change
This one is pretty straight forward. Thanks to Marc Shaw for showing the right way to refill, its a straight copy of a picture I saw in his winter maintenance thread.
1990 C4 5-speed gearbox:
1)Drop the rear engine cover if you still have it. There is another lower cover you can remove, if you wish, but its not necessary, it is just a bit directly under the fill port. I didn't remove it because my lift arms were blocking its removal.
2)There are two allen plugs, one is fill, one is drain. You loosen the upper fill one first to make sure that's not stuck because if you drain first and can't open the fill plug, well then you are screwed. Its a 10mm allen key.
3)Drain the gearbox. Then re-install the drain plug, 30Nm (22 ft-lbs)
4)You can do the rennlist searches yourself, but I settled on using Mobil Delvac 75W90 synthetic gear oil.
I got it here with free shipping: Drillspot.com
I ended up buying 2, 1 gallon containers, one for the rear, and one for the front.
5)Get yourself a nice funnel and about 5ft of clear hose and attach the two together. Put the tube end into the fill hole and then snake it out to the side of the car (see pictures below) and pour the oil into the funnel until you see it spill out of the fill hole. Remove the fill tube, let the excess drain, the torque in the fill plug to 30Nm (22ft-lbs).
C4 Front Differential Oil Change
1)Remove lower cover underneath the front diff (check out the condition of your CV boots and joints at this time)
2)Just like the rear, there are two allen plugs, one is fill, one is drain. You loosen the upper fill one first to make sure that's not stuck because if you drain first and can't open the fill plug, well then you are screwed. Its a 10mm allen key.
3)Drain the gearbox. Then re-install the drain plug, 30Nm (22 ft-lbs)
4)Refill using the same procedure as the 5 speed gearbox. Torque the fill plug to 30Nm (22ft-lbs) Re-install front under tray.
1990 C4 5-speed gearbox:
1)Drop the rear engine cover if you still have it. There is another lower cover you can remove, if you wish, but its not necessary, it is just a bit directly under the fill port. I didn't remove it because my lift arms were blocking its removal.
2)There are two allen plugs, one is fill, one is drain. You loosen the upper fill one first to make sure that's not stuck because if you drain first and can't open the fill plug, well then you are screwed. Its a 10mm allen key.
3)Drain the gearbox. Then re-install the drain plug, 30Nm (22 ft-lbs)
4)You can do the rennlist searches yourself, but I settled on using Mobil Delvac 75W90 synthetic gear oil.
I got it here with free shipping: Drillspot.com
I ended up buying 2, 1 gallon containers, one for the rear, and one for the front.
5)Get yourself a nice funnel and about 5ft of clear hose and attach the two together. Put the tube end into the fill hole and then snake it out to the side of the car (see pictures below) and pour the oil into the funnel until you see it spill out of the fill hole. Remove the fill tube, let the excess drain, the torque in the fill plug to 30Nm (22ft-lbs).
C4 Front Differential Oil Change
1)Remove lower cover underneath the front diff (check out the condition of your CV boots and joints at this time)
2)Just like the rear, there are two allen plugs, one is fill, one is drain. You loosen the upper fill one first to make sure that's not stuck because if you drain first and can't open the fill plug, well then you are screwed. Its a 10mm allen key.
3)Drain the gearbox. Then re-install the drain plug, 30Nm (22 ft-lbs)
4)Refill using the same procedure as the 5 speed gearbox. Torque the fill plug to 30Nm (22ft-lbs) Re-install front under tray.
Last edited by RicardoD; 12-06-2011 at 02:27 PM.
