Break-in for C3 differential?
Melting Slicks
Joined: Nov 2006
Posts: 3,409
Likes: 1,821
From: Apple Valley, MN
Take a nice and easy 15-20 mile drive, keeping the speed under 60 Mph. Find a parking lot and do several slow figure 8s. Let the differential cool. Repeat 2-3 more times.
No hard launches, no prolonged running at constant speed for 500 miles.
Drain the fluid, refill with Lucas 85W-140 gear oil with 2 bottles of Delco 10-4003 additive.
No hard launches, no prolonged running at constant speed for 500 miles.
Drain the fluid, refill with Lucas 85W-140 gear oil with 2 bottles of Delco 10-4003 additive.
Thread Starter
Race Director
Joined: Nov 2018
Posts: 13,228
Likes: 79
Take a nice and easy 15-20 mile drive, keeping the speed under 60 Mph. Find a parking lot and do several slow figure 8s. Let the differential cool. Repeat 2-3 more times.
No hard launches, no prolonged running at constant speed for 500 miles.
Drain the fluid, refill with Lucas 85W-140 gear oil with 2 bottles of Delco 10-4003 additive.
No hard launches, no prolonged running at constant speed for 500 miles.
Drain the fluid, refill with Lucas 85W-140 gear oil with 2 bottles of Delco 10-4003 additive.
Racer
Joined: Aug 2024
Posts: 278
Likes: 172
From: Pikes Peak region Colorado
2025 C3 of the Year Finalist - Modified
I have always been of the mentality if its going to break it will break right away... while it is still under warranty. Besides there is nothing like a nice long burn out!
Le Mans Master
Joined: May 2007
Posts: 5,025
Likes: 1,120
From: North tonawanda NY
These cars were new they were driven and "broken in " like this with another fluid change in the first 500miles? I just pulled my original rear end at 110k to swap in a 3.55 rear end and assumed if it was properly assembled with proper lash and clearances that it would be fine... I mean my old one still is? I did use the Lucas gear oil and gm limited slip additive.
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Thread Starter
Race Director
Joined: Nov 2018
Posts: 13,228
Likes: 79
Melting Slicks
Joined: Nov 2006
Posts: 3,409
Likes: 1,821
From: Apple Valley, MN
Thread Starter
Race Director
Joined: Nov 2018
Posts: 13,228
Likes: 79
I wonder why all manufacturers didn't consistently put a drain plug in - seems like something obvious to facilitate keeping fresh fluid in them.
Racer
Joined: Aug 2024
Posts: 278
Likes: 172
From: Pikes Peak region Colorado
2025 C3 of the Year Finalist - Modified