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Discussion Starter #1
Just changed my front and rear diff fluid and didn't use as much fluid as I expected. Figured i'd post my experience in case someone else uses less than they expect and gets worried.

This was done on a level surface and rear diff fluid was re-checked after a test drive and sitting over night.

Capacities:
Front Diff = 1.8 qt = ~57.6 oz
Rear Diff = 2.3 qt = ~75.2 oz
TOTAL = 4.1 qt = 131 oz (dropped the .2 off.. its close enough and used the sum of the quarts instead of sum of ounces)

Starting fluid volume:
75w140 Gear oil = 5 qt = 160 oz
Qty 2 4 oz Friction Modifier = 8 oz
TOTAL = 168 oz

Expected Leftover Fluid:
168-131 = 37 oz (1.15 qt)

Actual Leftover Fluid:
57 oz (~1.8qt)

Difference:
57-37 = 20 oz (5/8 of a quart)

In other words I expected to have a bit over 1 quart left. That's why i ordered 5 quarts; accidentally spill one or something and i'd still be good. Having a bit more than 1/2 quart than expected caught me a bit off guard... but I triple checked everything and it's good to go.

There's no hidden questions in this post... more of an FYI. There's a whole lot of reasons that diff quantities will vary. One thing I normally do that I didn't this time was to spin the carrier to try and get any trapped fluid out (that could easily account for some of the difference).
 

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Thanks for the information. I just changed my transfer case fluid yesterday, next step is the differentials. Where did you get your fluids from? The auto stores don't carry the fluid I need. When I do find it there's only Valvoline for $20 per quart. I'm going to order the Amsoil fluid tonight.
 

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Discussion Starter #3
I just order Amsoil online. It usually shows up the next day because they have distribution centers all over the place. FYI, if you use it for oil changes too its probably worth paying the $20/year to be a preferred member. I saved $30 alone by ordering a case of 5W20 OE oil and the diff + t-case fluids.
 

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I drained and filled my front diff on level ground, and I ended up filling the front diff a good 8 ounces before the published capacity.

Others have posted, that when they drained the diff with the front end elevated and properly supported, that they ended up filling to full capacity.

So, at least in my one time experience, it looks like the front diff will trap some fluid and NOT fully drain if its level, you have to jack up the front end to get it all out of the drain port.
 

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One of you guys should take pics and do a "how to" thread on this, Dealership asked for over 400 to do mine.
 

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jiffy lube. 289 bucks for a radiator flush, tran flush and fill, front and rear diffs, and the limited slip additive. I am in mid missouri so it may be different where you are but it sure as hell beats the dealer.
 

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Discussion Starter #8
One of you guys should take pics and do a "how to" thread on this, Dealership asked for over 400 to do mine.
The front diff and the t-case are seriously easier than doing an oil change...

1) Take off fill plug (always do this first)
2) Take off drain plug... let fluid drain
3) Replace drain plug
4) Fill with fluid to proper level (a $10 bottle pump makes this task EASY)
5) Replace fill plug

Only thing "slightly" more difficult with the rear diff is taking the cover off and cleaning everything to get a good seal with the new gasket maker. It's not really hard to do... just a bit more time consuming.

I'll do a write up in 15k miles :)
 

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The front diff and the t-case are seriously easier than doing an oil change...

1) Take off fill plug (always do this first)
2) Take off drain plug... let fluid drain
3) Replace drain plug
4) Fill with fluid to proper level (a $10 bottle pump makes this task EASY)
5) Replace fill plug

Only thing "slightly" more difficult with the rear diff is taking the cover off and cleaning everything to get a good seal with the new gasket maker. It's not really hard to do... just a bit more time consuming.

I'll do a write up in 15k miles :)
That's how I just changed mine two weeks ago. $50 in fluid, $10 lift rental and two hours later, all done and $300 saved! :D
 

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The front diff and the t-case are seriously easier than doing an oil change...

1) Take off fill plug (always do this first)
2) Take off drain plug... let fluid drain
3) Replace drain plug
4) Fill with fluid to proper level (a $10 bottle pump makes this task EASY)
5) Replace fill plug

Only thing "slightly" more difficult with the rear diff is taking the cover off and cleaning everything to get a good seal with the new gasket maker. It's not really hard to do... just a bit more time consuming.

I'll do a write up in 15k miles :)
I just did the rear diff and T-case yesterday. Here's a couple of things I learned (I'm a noob at doing this, so it's all new to me!) 1) The gasket maker has to say that it is made for gear oil. There were 6 different gasket makers at the parts store: black, blue, clear, grey, copper and red. None of them were the right one. I asked the parts guy and he gave me one that said it was purpose made to resist gear oil. 2) When I had the back diff cover off and the diff had fully drained I got curious and wanted to see the gears work, so I spun one tire with my foot. To my surprise about 2-3 more ounces of fluid squirted out of a little cylinder that has a wire lead coming out of it. I guess it's an actuator of sorts and the fluid was trapped inside the clutches. Someone correct me here because it's a WAG on my part as to what that cylinder is. Anyway, that bit of luck helped drain fluid which would have otherwise stayed in the diff.
The $10 pump worked awesomely. Someone posted that he got it from Harbor Freight Tools. That's where I got mine. IMHO it's a mandatory bit of kit for the DIY. I cleaned every bit of old gasket, grime etc off both the diff and the cover using a scrapper, a Dremmel with a soft metal brush bit and brake cleaner. I just made sure to cover the gears with a shop towel to keep debris from getting in there. Both mating surfaces were perfectly clean when I got done.
The Tcase was super easy to drain. Filling it was a snap using that pump. No reason to pay someone a pile of money for such an easy job. I took my time and spent the afternoon at it. Next time, I should have it done in half the time. Looking forward to your write-up. Cheers
 

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Discussion Starter #11
1) The gasket maker has to say that it is made for gear oil.
YES. You must get the correct stuff or the additives could break down the gasket and cause leaks (ive seen it more times than i can count fingers and toes).

Also, you should follow the directions on the package carefully. I do my rear diff first to give the gasket plenty of time to cure before filling it.
 

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That's what I did. The instructions said to put the diff cover on, tighten until a bead of squeeze-out is visible and wait an hour before applying final torque. I checked this morning and the seal is tight as a drum. I didn't do the front diff because there is a leak in a shaft seal and it's a covered repair; so I'll take it in and have the shop replace my diff fluid. BTW, do you take the front diff cover off when you replace the fluid or just drain and refill?
 

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That's what I did. The instructions said to put the diff cover on, tighten until a bead of squeeze-out is visible and wait an hour before applying final torque. I checked this morning and the seal is tight as a drum. I didn't do the front diff because there is a leak in a shaft seal and it's a covered repair; so I'll take it in and have the shop replace my diff fluid. BTW, do you take the front diff cover off when you replace the fluid or just drain and refill?
No, just drain and fill using the proper holes.

BTW, I love your signature quote!
 

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Likewise. Cheers
 

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Thank you guys for posting this topic! I went to the dealership yesterday to get a quote for these things and they are asking too much money.. I will do it myself when the weather gets better.
 
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