Rear Differential Drain
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
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.
Last edited by ch@0s; Mar 20, 2012 at 02:43 PM.
Race Director
Joined: Jan 2012
Posts: 17,062
Likes: 166
From: United States
I am an ASE certified mechanic sir and I would be willing to bet money I'm not the only one here that is.Your opinion could cost someone. I don't think he was asking for a wild guess he was asking from guidance from someone who knows what they are talking about ASE certified or not.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
..... WW
Melting Slicks
Joined: Nov 2005
Posts: 2,736
Likes: 0
From: WAY UPSTATE NY
...Exactly..It's pretty clear that the guy who says don't change it is a cheapskate...
Lets see..$25 plus shipping for the anylisis..They tell you Yep it needs to be changed..$35 for gear oil and Posi additive...Sixty bucks plus shipping...Real good advice here..
To the OP..Do you have a West Marine or a boatyard near you? If so look in the store for the Hand pump for filling outdrives..It screws on to quart bottles. Get a piece of tubing that fits over the pumps intake tutube at your loccal hardware store...Pull the fill plug out and shove the tube into the diff and pump the old fluid out.That same tube will fit on the dicharge end of the hand pump. Put that end in the fill hole of the diff ...Screw the hand pump on the quart bottle and pump the new gear oil into the diff..You can stop 1/2 way and add the Posi additive to the gear oil bottle and finish filling...PM me if this is unclear...
Oh and kracker...There a lot of ASE Certified Techs on here....Just Sayin'
Race Director
Joined: Jan 2012
Posts: 17,062
Likes: 166
From: United States
...Exactly..It's pretty clear that the guy who says don't change it is a cheapskate... Lets see..$25 plus shipping for the anylisis..They tell you Yep it needs to be changed..$35 for gear oil and Posi additive...Sixty bucks plus shipping...Real good advice here..To the OP..Do you have a West Marine or a boatyard near you? If so look in the store for the Hand pump for filling outdrives..It screws on to quart bottles. Get a piece of tubing that fits over the pumps intake tutube at your loccal hardware store...Pull the fill plug out and shove the tube into the diff and pump the old fluid out.That same tube will fit on the dicharge end of the hand pump. Put that end in the fill hole of the diff ...Screw the hand pump on the quart bottle and pump the new gear oil into the diff..You can stop 1/2 way and add the Posi additive to the gear oil bottle and finish filling...PM me if this is unclear...
Oh and kracker...There a lot of ASE Certified Techs on here....Just Sayin'
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Yes it does. If you were a qualified, knowledgeable mechanic, you would know about the affects of the time on oil. Condensation corrosion, etc.
This seems to be a very common response on the forums when someone is proven wrong. "Don't be so serious man!" Der. People come here looking for good information. BE serious.
This seems to be a very common response on the forums when someone is proven wrong. "Don't be so serious man!" Der. People come here looking for good information. BE serious.
Race Director
Joined: Jan 2012
Posts: 17,062
Likes: 166
From: United States
Yes it does. If you were a qualified, knowledgeable mechanic, you would know about the affects of the time on oil. Condensation corrosion, etc.
This seems to be a very common response on the forums when someone is proven wrong. "Don't be so serious man!" Der. People come here looking for good information. BE serious.
This seems to be a very common response on the forums when someone is proven wrong. "Don't be so serious man!" Der. People come here looking for good information. BE serious.
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Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
I agree with Tom400CFI, folks come here for answers, not comedy. Save that stuff for OT.
Race Director
Joined: Jan 2000
Posts: 16,487
Likes: 25
From: USA. Northern Virginia
5 years ago I replaced the fluid in the pumpkin on my 94 Vette…it’s easy.
I bought an electric portable bilge pump for the job. They are available at marine supply shops. With the Vette high up on jack stands I took off the fill bolt on top of the pumpkin and feed in the siphon hose. I then turned on the pump, 4-7 minutes later the pumpkin was empty. I reversed the siphon hose and pumped in my new Mobil 1 rear axle oil with the GM additive to the level of the bottom of the fill hole.
The whole process took maybe an hour…and that was with the 12 oz of Guinness fluids that I added to myself when I was finished.
Need any more help…drop me a PM and I’ll walk you through it.
I bought an electric portable bilge pump for the job. They are available at marine supply shops. With the Vette high up on jack stands I took off the fill bolt on top of the pumpkin and feed in the siphon hose. I then turned on the pump, 4-7 minutes later the pumpkin was empty. I reversed the siphon hose and pumped in my new Mobil 1 rear axle oil with the GM additive to the level of the bottom of the fill hole.
The whole process took maybe an hour…and that was with the 12 oz of Guinness fluids that I added to myself when I was finished.
Need any more help…drop me a PM and I’ll walk you through it.
Thread Starter
Instructor
Joined: Jan 2008
Posts: 123
Likes: 0
From: Negaunee MI
69mako and nutz4c4 thank you for the information. I'd much rather find a boat store and get a pump than drill tap and hope it doesn't leak. It sounds like it still would be wise to change the fluid, yes? Does everyone agree 80w90 and the diff additive is still the best to put back in or is there something newer and better?
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
69mako and nutz4c4 thank you for the information. I'd much rather find a boat store and get a pump than drill tap and hope it doesn't leak. It sounds like it still would be wise to change the fluid, yes? Does everyone agree 80w90 and the diff additive is still the best to put back in or is there something newer and better?
Le Mans Master
Joined: Oct 2007
Posts: 9,682
Likes: 3,434
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
I have drilled and tapped my differential and it has been leak free for about 3 years or so. I change my oil once a year since I race it.
This is the oil I use and prefer:
AMSOIL Severe Gear 75W-90
It already has posi additive in it so no need to add any more. I put it straight into the diff and I have no issues with chattering or anything.
Amsoil also has a hand pump that comes with tubing to fit all their bottles:
http://www.amsoil.com/catalog.aspx?G...292?zo=1934716
This is the oil I use and prefer:
AMSOIL Severe Gear 75W-90
It already has posi additive in it so no need to add any more. I put it straight into the diff and I have no issues with chattering or anything.
Amsoil also has a hand pump that comes with tubing to fit all their bottles:
http://www.amsoil.com/catalog.aspx?G...292?zo=1934716
Thread Starter
Instructor
Joined: Jan 2008
Posts: 123
Likes: 0
From: Negaunee MI
I have drilled and tapped my differential and it has been leak free for about 3 years or so. I change my oil once a year since I race it.
This is the oil I use and prefer:
AMSOIL Severe Gear 75W-90
It already has posi additive in it so no need to add any more. I put it straight into the diff and I have no issues with chattering or anything.
Amsoil also has a hand pump that comes with tubing to fit all their bottles:
http://www.amsoil.com/catalog.aspx?G...292?zo=1934716
This is the oil I use and prefer:
AMSOIL Severe Gear 75W-90
It already has posi additive in it so no need to add any more. I put it straight into the diff and I have no issues with chattering or anything.
Amsoil also has a hand pump that comes with tubing to fit all their bottles:
http://www.amsoil.com/catalog.aspx?G...292?zo=1934716
Le Mans Master
Joined: Oct 2007
Posts: 9,682
Likes: 3,434
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11