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Diff. Fluid change ?

Hi All

A question for those of you who have changed there own diff fluid. I managed to get about 4 pints of oil in the diff. plus 4 0z of friction modifier before it started coming out the fill hole. The owners manual calls for 5 pints. Do you think I have enough in .

I am thinking the race ramps ( which are 10 inches high) are causing the oil to come out prematurely .


Now that I put this down on paper (so to speak) I think I answered my own ? Perhaps I will put the ramps on the front wheels and add another 12 oz.
 
Which diff do you have? You don't need the friction modifer with the Torsen. If you use the front fill hole the angle might have added to the premature fill but not by much. Did you remove the diff cover to drain the fluid?
 
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5 DOT 0 said:
Which diff do you have? You don't need the friction modifer with the Torsen. If you use the front fill hole the angle might have added to the premature fill but not by much. Did you remove the diff cover to drain the fluid?

Hi 5 DOT 0,

I understand that the Torsen Diff unit doesn't use clutch plates like a limited slip, but having just been to my Ford dealer for the Track Key install, I picked up some more diff fluid(hoping for more that 12 hours of track time this season) and questioned the parts mgr about the fiction modifier that his Ford chart listed as being required. It did list it for the LS.
Is it in the Boss supplement that states the modifier is not required, or maybe from Ford Racing?
 

JScheier

Too Hot for the Boss!
What ^ said.

Also, if you pull the cover, you will notice that the flange of the diff is about 1/2" to 1" taller than the bottom of the differential. My guess is there is still some fluid left in there if you just 'drain' the diff by pulling the cover. I used suction to remove the last of the fluid, cleaned the diff out with brake parts cleaner, checked gear wear and pattern, buttoned it all back up and put just a little less than 5 pints in the differential when it started coming out the fill-hole. Car was level (on jack stands).
 
yea I pulled off the cover and cleaned out the bottom of the diff. I read on here that the friction mod. was not required but I put it in anyways. I think if the car was level I could get a bit more in.

Did any of you remove that bar that goes from one side of the axle to the other(I don't know what its called), I removed it to take the diff. cover off. Anyways if you did , did you notice there was something inside it. Sand or something a bit heaver than sand,seems the bar was about half full. may be something to do with handling.
 

steveespo

Lord knows I'm a Voodoo Child
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There is iron shot inside of the panhard rod. This is for noise/vibration and harshness dampening I replaced mine with an adjustable and had a clunking noise that I thought was the exhaust system hitting the body. Finally thought to change the panhard back and the noise was gone. My lowered 1" rear is 1/4" offset to the left , but quiet over the bumps.
Steve
 

Dvendet

Everyone's entitled to my opinion. ;)
5 DOT 0 said:
I had a shop install fill and drain plugs in my diff cover and they did remove the bar.

P1020819.jpg
Does Ford Racing or third party sell a replacement cover which has both plugs installed?
Also, is that cover the stock cover? Looks great and will save you work.

MMD
 

Dvendet

Everyone's entitled to my opinion. ;)
5 DOT 0 said:
MakeMyDay said:
Does Ford Racing or third party sell a replacement cover which has both plugs installed?
Also, is that cover the stock cover? Looks great and will save you work.

MMD
Thanks, it's the stock cover. FR does sell a cover but I'm not sure of the details, Pete has one on his Boss.

Do you think this might be it?

http://editiondigital.net/iphone/zoom.php?i=88199&p=170&s=0&x=963&y=956&ipad=1#_m0

see part # M-4033-G2 on bottom left of page.

Here is a better view.

http://www.latemodelrestoration.com/item/M4033G2/Ford-Mustang-FRPP-Rear-Differential-Girdle


Thanks.

MMD
 
Do you think this might be it?

http://editiondigital.net/iphone/zoom.php?i=88199&p=170&s=0&x=963&y=956&ipad=1#_m0

see part # M-4033-G2 on bottom left of page.

Here is a better view.

http://www.latemodelrestoration.com/item/M4033G2/Ford-Mustang-FRPP-Rear-Differential-Girdle


Thanks.

MMD

DO NOT use this cover on a Boss!! The OEM Boss cover has a vent in the top of it instead of using the more traditional axle tube vents (which are pinched closed on the Boss). If you use this cover - or a similar one with no vent, then the fluid will heat and force its way out between the housing and the cover. Don't ask me how I know this!
 
Here the link to the Boss/ GT500 cover http://www.latemodelrestoration.com/item/M4033K/1986-11-Mustang-Gt500-Style-Finned-Aluminum-Rear-End-Cover .
 
MakeMyDay said:
Do you think this might be it?

http://editiondigital.net/iphone/zoom.php?i=88199&p=170&s=0&x=963&y=956&ipad=1#_m0

see part # M-4033-G2 on bottom left of page.

Here is a better view.

http://www.latemodelrestoration.com/item/M4033G2/Ford-Mustang-FRPP-Rear-Differential-Girdle


Thanks.

MMD
I'm 99.999% sure that's it but you should double check before purchasing. Pete is using it and I'm not aware of any issues he may be having. I don't have any personal experience with that diff cover and with that said I don't think it's necessary and I'd follow Kendall's advice. Hopefully Pete will chime in with his experience.
 
I read somewhere that someone tried people tried using a gasket that came with the FRP one and it caused leaks.

CoolTechLLC said:
Do you think this might be it?

http://editiondigital.net/iphone/zoom.php?i=88199&p=170&s=0&x=963&y=956&ipad=1#_m0

see part # M-4033-G2 on bottom left of page.

Here is a better view.

http://www.latemodelrestoration.com/item/M4033G2/Ford-Mustang-FRPP-Rear-Differential-Girdle


Thanks.

MMD

DO NOT use this cover on a Boss!! The OEM Boss cover has a vent in the top of it instead of using the more traditional axle tube vents (which are pinched closed on the Boss). If you use this cover - or a similar one with no vent, then the fluid will heat and force its way out between the housing and the cover. Don't ask me how I know this!

Lots of people seem to be using the basters on the axle vents, so it should work if you open them. I have an expansion tank from the other thread but haven't installed it yet.
 

Dvendet

Everyone's entitled to my opinion. ;)
5 DOT 0 said:
MakeMyDay said:
Do you think this might be it?

http://editiondigital.net/iphone/zoom.php?i=88199&p=170&s=0&x=963&y=956&ipad=1#_m0

see part # M-4033-G2 on bottom left of page.

Here is a better view.

http://www.latemodelrestoration.com/item/M4033G2/Ford-Mustang-FRPP-Rear-Differential-Girdle


Thanks.

MMD
I'm 99.999% sure that's it but you should double check before purchasing. Pete is using it and I'm not aware of any issues he may be having. I don't have any personal experience with that diff cover and with that said I don't think it's necessary and I'd follow Kendall's advice. Hopefully Pete will chime in with his experience.

I am interested in finding a replacement cover that already has a fill & drain plug. If I can't find one I'll just have to drill & tap it myself. What size drill bit did you used in your stock cover? Where can I get drain plugs that would work for this app?

How many miles did you go before you first drained & filled the differential on your Boss?

MMD
 
Dealer wants $275 to do a diff fluid change, that seems high to me considering I got full drivetrain fluid swaps in my Evo for less (tranny, tc, diff). Is that too high or is it just because it doesn't have a drain hole? They claimed you have to crack the cover to do the change, you can't do it with a pump.
 

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