[Giri]

Hi Guys,

I'm about to hit 25k miles and was wondering if I should change the differential fluid myself? I have the automatic and 4 cylinder LTG engine.

I do not track my car.

I've been doing oil changes on my own and had two questions:

1- How hard is it to change compared to oil?
2- What are the benefits of changing now vs at 45k miles like the service guide calls for?

[EagleRS]

I woudn't wait until 45K miles if you are beating the car on back roads and getting "4 mpg" on back roads. I changed mine at 37K miles and it was nice and black!

It's not difficult what so ever, if you have a way of putting the car on ramps then great, if not, you can lift it from the bump bar that is located right behind the differential.

There is a video somewhere on here that shows a guy changing his fluid on his 1SS, same exact concept just different fluid spec. and capacity. Rule of thumb is pump enough in there until it starts to drip out.

Let me know if you have any questions about it, it's a simple fun task to do....

[soloknight6]

I'd say change it. Not sure how to do it on the turbo motor, but it should be about the same level of difficulty as an oil change.

[Corner carver]

Not hard at all, if you can change your oil the diff is no big deal... You'll just need a fluid transfer pump to put the fluid back in; can find them cheap on ebay.

I changed my rear diff fluid to red line after about 6000km and found some fairly nasty sludge on the magnetic drain plug... Also had a bit of that rear end grind people have been reporting; the fluid change took care of 80% of this... I'll change it again in the spring and hope the grinding is gone completely.

Car only has 6-8000km put on a year.

Can't claim to know the 'benifits' but I know with how I drive (and you by the sounds of it) that an early fluid swap to a high end fluid is cheap insurance.

Once you're a millionaire spread the wealth around to peeps who helped you out on the forum *wink wink

Lift car, remove top plug, remove bottom plug and drain fluid.
Clean off bottom plug and reinstall, pump fluid back into top hole until a little dribbles out, reinstall top plug.

I turned about a dozen figure eights in each direction to work it in a bit.

Burnout.
Beer.
Done.

[Giri]

Thank you guys. Plan to it next week

[Giri]

I just changed my rear diff fluid. 1 inch long sludge buildup on bolt.

What's weird is that I only got 0.6 quarts out. I tried putting more in but it won't take more than 0.6q - and I let it drip for a long time. Did I do something wrong?

The car wasn't level when I did it, but the fill plug was higher than drain, so if anything it should have taken more rather than less?

[soloknight6]

Originally Posted by Giri

I just changed my rear diff fluid. 1 inch long sludge buildup on bolt.

What's weird is that I only got 0.6 quarts out. I tried putting more in but it won't take more than 0.6q - and I let it drip for a long time. Did I do something wrong?

The car wasn't level when I did it, but the fill plug was higher than drain, so if anything it should have taken more rather than less?

The capacity for the auto diff in the V6 model is 0.53qts. Im certain the 4cyl and 6cyl autos share the same driveline, including the diff.

[Dustya]

If you look through the manual it tells you how much fluid you need and what fluid you need to buy. Just in case you forget in the future its a great reference to have. Also not sure how you changed it but harbor freight has a great siphon pump that works great for adding fluid back in.

[Giri]

Originally Posted by soloknight6

The capacity for the auto diff in the V6 model is 0.53qts. Im certain the 4cyl and 6cyl autos share the same driveline, including the diff.

Thank you so much! I really appreciate it.

I might have overfilled it a bit since I closed the fill hole while it was still flowing out + My car was jacked up in the back with the front already being half a foot lower than the mid point. What are the dangers of overfilling?

[soloknight6]

Originally Posted by Giri

Thank you so much! I really appreciate it.

I might have overfilled it a bit since I closed the fill hole while it was still flowing out + My car was jacked up in the back with the front already being half a foot lower than the mid point. What are the dangers of overfilling?

You did not really overfill. Old rule of thumb when filling diffs: "fill until oil slowly drips from the fill plug."

You may have added 0.6qts, but if some flowed out, it would have been closer to the 0.53 mark. You did no harm.

[NowaChevyGuy]

Originally Posted by soloknight6

The capacity for the auto diff in the V6 model is 0.53qts. Im certain the 4cyl and 6cyl autos share the same driveline, including the diff.

They actually are different. The V6 RS models come with a I believe 266 gear ratio and the manual 2.0 turbo comes with a 3.23 limited slip differential. I did this swap in my V6 so I definitely know. Can't recall how much fluid it took but the 3.23 with LSD is way awesome in the V6.

[LtColumbo]

Originally Posted by NowaChevyGuy

They actually are different. The V6 RS models come with a I believe 266 gear ratio and the manual 2.0 turbo comes with a 3.23 limited slip differential. I did this swap in my V6 so I definitely know. Can't recall how much fluid it took but the 3.23 with LSD is way awesome in the V6.

My Mercury Grand Marquis came with the standard 2.73:1 rear-end gears. The Crown Vic Interceptor has 3.27:1 rear-end gears.



On a long trip from CA to CO, the stock gears were great for high-speed cruising on level ground, but sucked going up hills and a high altitudes.



After a bit of research, I had 3.55:1 gears put in. OMG! Burnouts in first, and a big chirp on the shift to second and the rear end would step out! It would pull strong on hills on the freeway and rarely shift out of 4th OD in doing so. I have a friend who has several CV Interceptors. He drove my car with the 3.55:1 gears and exclaimed, "WOW! This is much faster than mine!"



With the 2.73:1 gears, the engine was turning 1900 RPM @80 MPH. With the 3.55:1 gears, it was turning 2500 RPM @80 MPH. Not nearly as "relaxed." And I lost about 3 MPG on the highway.

[WhiteMale]

Make sure you buy this hand operated pumper that threads on to the bottle

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1