Rear Differential Drain
03-19-2012, 03:38 PM
#1
Instructor
Thread Starter
Rear Differential Drain
Am i missing something or is there no drain plug for the rear diff on a 95 C4? I found the fill, And i don't want to take the axle out to change the fluid. Granted it does only have 34,000 for a 95 but i'm sure putting in fresh fluid can't hurt anything.
03-19-2012, 03:42 PM
#2
There is no drain. Some people have very carefully drilled and tapped it to add one. If you don't want to do that you can crack open the seal to drain it then hope you can put it back and it not leak. Finally the cheapest and least likely to cause trouble option is to suck the fluid out through the fill hole.
03-19-2012, 03:57 PM
#3
Le Mans Master
There is no drain. Some people have very carefully drilled and tapped it to add one. If you don't want to do that you can crack open the seal to drain it then hope you can put it back and it not leak. Finally the cheapest and least likely to cause trouble option is to suck the fluid out through the fill hole.
...
...WW
03-19-2012, 04:16 PM
#4
Melting Slicks
03-19-2012, 04:47 PM
#5
Race Director
That oil doesnt need to be changed. My opinion. I recommend if you do change it get a Oil Analysis from Blackstone Labrotories and see what they say. i bet they say its almost new and is in perfect condition.
03-19-2012, 06:21 PM
#7
Melting Slicks
I bet the analysis would cost you more than fresh gear oil and posi additive.
03-19-2012, 06:26 PM
#8
Race Director
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Mine did, at about 60K miles. The clutch plates started moaning during tight turns. Replacing the diff lube cured it and it should be good to go for the duration.
Open diffs can go seemingly forever without a lube change. Limited-slip units, not so much.....
__________
not easily impressed....
Open diffs can go seemingly forever without a lube change. Limited-slip units, not so much.....
__________
not easily impressed....
03-19-2012, 06:39 PM
#9
Safety Car
Especially, if you do any kind of aggressive driving auto-x, track, 1/4 mile, etc...
03-19-2012, 07:43 PM
#10
Race Director
Mine did, at about 60K miles. The clutch plates started moaning during tight turns. Replacing the diff lube cured it and it should be good to go for the duration.
Open diffs can go seemingly forever without a lube change. Limited-slip units, not so much.....
__________
not easily impressed....
Open diffs can go seemingly forever without a lube change. Limited-slip units, not so much.....
__________
not easily impressed....
Regardless, changing oil just because you feel it is bad is wasteful. Have a sample tested, for 25 bucks. They will tell you the condition of the oil and contaminants within the oil.
But if people just want to change oil to change oil, its your money. If you dont know if something is worn with the oil, or within the parts, you are just wasting money in the long run. Its my opinion, nothing more.
I would be more concerned of 17 year old antifreeze and brake fluid, than my differential fluid.
Last edited by krackenvette; 03-19-2012 at 09:13 PM.
03-20-2012, 12:23 AM
#11
Instructor
Thread Starter
I did replace the antifreeze and the trans fluid this weekend and the brake fluid was about 3 years ago. Once i new it wasn't a simple drain and fill i decided not to mess with the diff. Thanks for all the help guys and gals!!!
03-20-2012, 03:32 AM
#12
Race Director
03-20-2012, 05:13 AM
#14
For what it is worth I will point out that Chrysler specified a 12,000 mile change interval for differential lube on Viper which used a nearly identical D44. Yes, that might be overkill, but as others point out changing lubricant is cheap insurance.
See my post #4 in this link for the procedure to install what GM forgot on the C4.
http://forums.corvetteforum.com/c4-t...questions.html
See my post #4 in this link for the procedure to install what GM forgot on the C4.
http://forums.corvetteforum.com/c4-t...questions.html
03-20-2012, 08:55 AM
#15
Instructor
Thread Starter
For what it is worth I will point out that Chrysler specified a 12,000 mile change interval for differential lube on Viper which used a nearly identical D44. Yes, that might be overkill, but as others point out changing lubricant is cheap insurance.
See my post #4 in this link for the procedure to install what GM forgot on the C4.
http://forums.corvetteforum.com/c4-t...questions.html
See my post #4 in this link for the procedure to install what GM forgot on the C4.
http://forums.corvetteforum.com/c4-t...questions.html
Awesome thank you this helps a lot.
03-20-2012, 08:59 AM
#16
Instructor
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03-20-2012, 09:02 AM
#17
It's just called cheap insurance. I just changed the oil in my dad's 1946 Chevy pickup, it only had 900 miles on it, but it was 5 years old. Call me crazy but I'll spend the $20 to change it just in case there were contaminants in the old oil that might cost an engine. Back on the subject of the differential, consider worst case $100. If you're not willing to spend $100 every 17 years, maybe you shouldn't own a Corvette, or any car for that matter.
03-20-2012, 01:07 PM
#18
Race Director
03-20-2012, 02:04 PM
#19
Le Mans Master
Did you have an oil analysis done? There is the oil and the gm additive. I bet the additive wore out.
Regardless, changing oil just because you feel it is bad is wasteful. Have a sample tested, for 25 bucks. They will tell you the condition of the oil and contaminants within the oil.
But if people just want to change oil to change oil, its your money. If you dont know if something is worn with the oil, or within the parts, you are just wasting money in the long run. Its my opinion, nothing more.
I would be more concerned of 17 year old antifreeze and brake fluid, than my differential fluid.
Regardless, changing oil just because you feel it is bad is wasteful. Have a sample tested, for 25 bucks. They will tell you the condition of the oil and contaminants within the oil.
But if people just want to change oil to change oil, its your money. If you dont know if something is worn with the oil, or within the parts, you are just wasting money in the long run. Its my opinion, nothing more.
I would be more concerned of 17 year old antifreeze and brake fluid, than my differential fluid.
To the OP please change your oil you will feel better about it and so will I.
03-20-2012, 02:38 PM
#20
Race Director
I guess we aren't as smart *** you. But the point should be taken that after 17 years someone decides to change diff oil. And 34,000 miles. Time vs actual use. Regardless, we all have our advice, and opinions. Its a forum, not an ASE certified mechanics thread. Its just that, nothing more.