Differential Fluid Change - Whats the process?

[eabrillon1978]

My viper has a Quaife with a Mopar rear differential cooler installed. Cars down for a little bit and I wanted to change out the fluid since it's been a while.


Anyone familiar with the procedure, and was curious how many quarts to fill it? What type of fluid do you recommend?

 

[Fatboy 18]

On a normal diff you stick a plastic tube into the filler hole then push it down to the lowest part of the diff then **** out the old fluid using some form of vacuum pump. I'm just on my way to the garage now to do this very thing

To re-fill using a clean plastic tube fill until fluid comes out of the filler hole

I'm not sure how you would perform the task on your set up? I guess it would also depend weather the cooler rad, was higher than the diff? I'm sure someone out there would know.

 

[Darth Menace]

I know when I did the rear end fluid on my town car there was fluid plus a amount of differential slip or something like that. Is this required for the viper too?

 

[eucharistos]

friction modifier, yes (gen 1,2,4 4oz i think....gen 3 varying opinions)

 

[eabrillon1978]

Appreciate the replies. That's what I kind of guessed. What I'm trying to figure out is how much fluid actually goes in. Normally you would stop when it comes out of the fill plug, but because it has the cooler on there, I don't really know how much extra I need.

What type of fluid do you recommend or do I stay with the OEM Mopar fluid and limited slip additive?

 

[roller]

I would use the Mopar fluid, but with the Quaife differential you shouldn't need the friction modifier as there are no clutches in their differentials. I would fill to the plug level, drive the car and recheck the level.

Frank

 

[Fatboy 18]

Have to admit the last time I changed my fluid I used Amsoil Severe gear oil 75w-140 fully synthetic, http://www.amsoil.com/storefront/svo.aspx I did not bother with adding mopar friction modifier. Seemed to work just fine? But if you read down further on the Amsoil spec sheet, they do their own additive should you need it

 

[Stonep185]

A normal diff holds 41oz. but I'm unsure how much your cooler holds. +1 on the amsoil severe gear, my car is now full amsoil. I added non slip as well and no complaints here. I'm in alb all week if you need a hand, its a messy job

 

[Camfab]

This is just me, but I'm guessing your not the owner that added the quaife or the cooler. Not knowing how old the fluid is would push me into a full disassembly and cleaning of the cooler and the lines. The cooler is on a thermostat so just filling the diff. and driving may not actually get you to the actual correct level. Disassemble everything and flush out cooler and lines. No chemicals in pump. Reassemble cooler assembly and if possible by pass thermostat and prime the system with fresh Mopar synthetic axle fluid. I'd run it till fluid pumped out the return line for a few seconds. I'd then connect the suction side to the diff. and pull the AN fitting off the side of the diff and fill till it flows out. Put the AN fitting back in (fresh teflon tape on the second thread back and beyond), on the return side and hook up your line to it. Viola! (FYI, I know nothing about this system , but this is what I'd do)

I believe I read years ago that the system was made by Tilton, you could call them and see if my thoughts are legitimate in process. I also remember hearing that the pumps were prone to failure, does yours work? I wanted that system but it was no longer available when I tried to purchase it eight or nine years ago. good luck

 

[eabrillon1978]

Correct you are! This was in the car when I purchased it, prior owner was into autocross, he passed away and I unable to get any info about it. I think you have a good point, I'll try to get a hold of them and see if I can get some info on the correct procedure, if not I'll try just what you said. Im pretty sure it works still, it's connected to a light on my dash that turns on when fluid is cool and then turns off when it's hot, when cool again it comes back on. I'm actually out of town, so I'll have to do this when I get back. Thanks for the help!

Appreciate everyones help on this!!

 

[eabrillon1978]

A normal diff holds 41oz. but I'm unsure how much your cooler holds. +1 on the amsoil severe gear, my car is now full amsoil. I added non slip as well and no complaints here. I'm in alb all week if you need a hand, its a messy job

Really appreciate the help, I'm actually out of town right now and not going to be back for a couple weeks, very nice of you to loan a hand.

 

[Darth Menace]

I plan on doing this soon too with amsoil (I use amsoil everything in all my vehicles), but is friction modifier required for the viper rear end?what are the pros and cons of not using it?

 

[Stonep185]

Darth M, I'll be back in fw next week so I'll offer YOU an extra hand lol let me know if you need a good deal on amsoil. If the diff clutches make a popping noise you need the additive but if not then I've heard its not necessary. I don't know the technical side of it. Many new synthetics say its not necessary but I add it anyway...

 

[Darth Menace]

Stonep- thanks for the offer on amsoil, but right now I have the preferred membership and I pick it up at the warehouse (saves a tonne not paying for shipping).

This will be on my to do list for sure

 

[dave6666]

If you need the friction modifier... pump it in first. And not all clutch diffs need the modifier. My Giken does not.

 

[AZTVR]

I plan on doing this soon too with amsoil (I use amsoil everything in all my vehicles), but is friction modifier required for the viper rear end?what are the pros and cons of not using it?

If the diff clutches make a popping noise you need the additive but if not then I've heard its not necessary. I don't know the technical side of it. Many new synthetics say its not necessary but I add it anyway...

Like Stonep185 said, I'd agree that since you are putting an untested (by the Viper engineers) fluid in your differential, you will just have to experiment with how the clutches in the diff act, and go from there.

Here's a good post: http://forums.viperclub.org/threads...ion-Modifier?p=2041204&viewfull=1#post2041204

 

[Darth Menace]

Like Stonep185 said, I'd agree that since you are putting an untested (by the Viper engineers) fluid in your differential, you will just have to experiment with how the clutches in the diff act, and go from there.

Here's a good post: http://forums.viperclub.org/threads...ion-Modifier?p=2041204&viewfull=1#post2041204

thanks..i guess either way put it in and be happy or test it and add it later.

 

[All Blue ACR]

Make life easier, things are tough enough....

You must be registered for see images attach

 

[Darth Menace]

what viscosity do we use?

 

[dave6666]

what viscosity do we use?

What diff do you have?

 

[ViperTony]

Make life easier, things are tough enough....

You must be registered for see images attach

By far, one of the best mods I've done. http://forums.viperclub.org/threads/606920-Viper-Differential-Drain-Plug-Install-by-Jerry-Scott Not terribly difficult to do.

 

[Darth Menace]

What diff do you have?

I don't know.......just the factory 98 gts rear end

 

[dave6666]

I don't know.......just the factory 98 gts rear end

Then use the factory fill.

 

[Darth Menace]

I'm using amsoil, so I have to know which viscosit to buy

 

[ViperTony]

The factory fill is 75w-140. https://www.viperpartsofamerica.com...dodge-viper-synthetic-gear-lubricant-04874469 Hope this helps.

 

[Darth Menace]

Just the answer I was looking for! Thanks..............

 

[Darth Menace]

is this the drain screw? [IMG=http://img22.imageshack.us/img22/4444/20130125164416.jpg][/IMG]

 

[AZTVR]

That's it. You will need something to **** the fluid out of there with (or to at least start a siphon effect.)

 

[Darth Menace]

10-4 thanks. I will use the same siphon I use to get my free gas

That's it. You will need something to **** the fluid out of there with (or to at least start a siphon effect.)

 

[Darth Menace]

that sure doesnt look like 41oz can fit in there before the hole