help, diff fluid change
Thread Starter
Racer
Joined: Aug 2004
Posts: 395
Likes: 1
From: Dartmouth Massachusetts
help, diff fluid change
my drain plug on the diff was easy to break loose, but the fill plug is insanely tight, can't break it.. am i doing something wrong? is it reverse thread? i don't want to strip the head, and am afraid to if i keep wailing away on it
no need to worry too much, i didn't drain it yet, but i'd like to get it done since i have the car up...
no need to worry too much, i didn't drain it yet, but i'd like to get it done since i have the car up...
Drifting
Joined: Jul 2001
Posts: 1,896
Likes: 3
From: New Bern NC
Should not be reverse thread, as I recall. On both the C5 & C6, the tranny plugs were very tight as they had a red thread locker on them. They will break loose with a snap. Get a long breaker bar or pipe extension. Worked for me.
Melting Slicks
Joined: Mar 2001
Posts: 2,117
Likes: 1
From: El Paso TX
Anytime I have changed fluids on previous cars I always attempt to loosen the fill plug before the drain plug. That way you avoid the trouble of leaving the car inoperable. Good for you for not draining it yet. 
Hopefully this saves someone else trouble in the future.
Get an extension and it should come off.
Matt
Hopefully this saves someone else trouble in the future.Get an extension and it should come off.
Matt
Drifting
Joined: Apr 2006
Posts: 1,276
Likes: 5
From: Ambler Pa.
Mine was also very tight. If I recall it is a metric hex recessed plug. I had to use a long 3/8 drive breaker bar and apply a heavy, sharp, snap to break it. It is normal right hand threads, so as you face the fill plug, counter clockwise to loosen/remove. Good luck.
Thread Starter
Racer
Joined: Aug 2004
Posts: 395
Likes: 1
From: Dartmouth Massachusetts
thanks for the corfirmation on the thread direction ended up getting it w/ a fairly long breaker bar and some clever repositioning to get some good force on it..
damn, that badd larry didn't want to come off...
on a side note... w/ the smaller flowmaster cans under there, i was able to just tip and squeeze the royal purple bottle in the hole and not worry about fumbling w/ a small fluid pump.
ended up getting it w/ a fairly long breaker bar and some clever repositioning to get some good force on it..damn, that badd larry didn't want to come off...
on a side note... w/ the smaller flowmaster cans under there, i was able to just tip and squeeze the royal purple bottle in the hole and not worry about fumbling w/ a small fluid pump.
Safety Car
Joined: Jan 2006
Posts: 4,598
Likes: 78
From: Miami FL
2020 C6 of the Year Finalist - Unmodified
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Valuable information
I changed the differential fluid BEFORE putting on the B&B Rt 66, so I had to use the pump-it-in method.
All who are looking at changing the fluid: The fill plug is REALLY TIGHT, and I needed a long pipe on the 1/2 inch breaker bar to get it loose.
And it does take a 10 mm hex drive. I mistakenly thought it was 3/8 inch SAE hex, and bunged up the plug pretty badly. That gave Fichtner the opportunity to sell me a shiny new replacement. Use the 10 mm hex and save your pennies.
All who are looking at changing the fluid: The fill plug is REALLY TIGHT, and I needed a long pipe on the 1/2 inch breaker bar to get it loose.
And it does take a 10 mm hex drive. I mistakenly thought it was 3/8 inch SAE hex, and bunged up the plug pretty badly. That gave Fichtner the opportunity to sell me a shiny new replacement. Use the 10 mm hex and save your pennies.
