Front Differential Fluild Change (1 Viewer)

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But the recovery was magnificent. You'll never be good at recoveries if you don't foul things up now and then.

Thanks for the kindness, and I guess there's some truth to what you say. On the other hand, I'd like to stick to fouling things up via methods that just aren't outright stupidity.... like,things that start with, "Hold my beer, watch this," at least, or "You know, I think there's a chance this could go well." Ramming things into your differential ... there's just no chance of that being a good time... at least, not unless you're watching from a distance!
 
Yeah, I had the magnetic plug where the magnet extended maybe 1/2"-3/4" out of the plug itself. When I got a new one from the dealer, based on the part number I looked up, it looked just like my old one. The transfer case plug had the low profile/recessed magnet on my truck.

I can laugh at it now. Then, not so much. Now... drilling out a broken EZout is today's fun.

Oh jeez that sucks. Yeah magnet supposed to be flush. Doh
 
Procedure for changing front differential fluid on a 100.

Draining:

Drive the vehicle to warm-up the gear oil. It’s best to raise the front of the vehicle to gain more working clearance. Ramps work well: http://www.autobarn.net/usm11905.html. Remove the rear splash pan, six 12mm bolts. Remove the fill plug first. It’s located on the passenger side of the differential housing. It has a 10mm Allen head (verify before starting job). Use an Allen socket on a racket to remove the fill plug. Be sure the Allen socket stays squarely in the plug head as pressure is applied to the racket handle, especially if a cheater pipe is used. Apply slow steady pressure so it doesn’t strip out. Remove the fill plug before the drain plug so in case the fill plug is frozen or stripped and won't come out you’re not faced with no gear oil in the housing and no way to refill. If the plug is frozen, spray it with PB Blaster brand penetrating oil and let it work for 15 minutes. Once the fill plug is removed, place a drain pan under the differential and remove the drain plug. It is located below the fill plug. Use the same Allen socket used on the fill plug.

Filling:

Remove the old sealing ring gaskets from the two plugs. Clean any metal particles off the magnet on the drain plug. There should only be a little finely ground metal dust (paste); no chips or chunks (i.e. broken gear teeth). Being able to see and evaluate the debris on the magnet first hand is one advantage of changing the fluid yourself. Clean both plugs with solvent and a wire brush so they look like new. Install new sealing ring gaskets. These are hollow aluminum, crush type gaskets. Don’t reuse the old ones! Coat the plug threads with anti-seize. Clean the sealing surface around the drain plug hole with a rag. Install the drain plug and torque to 35 foot-pounds. Fill the housing with new gear oil. There is not enough room to insert the nozzle of a 1 quart lube bottle into the fill hole and transfer directly from the bottle. At a minimum, a 4 foot piece of ¼” ID clear plastic tubing is needed. Force one end down over the nozzle on the lube bottle (don’t cut the nozzle back to short or the tube won’t stay on) and route the other end through the passenger side wheel well to the fill hole. Hold the tube in the fill hole and have an assistant invert and squeeze the bottle to fill the housing. As an alternative, purchase a lube pump that screws onto the lube bottle or a suction gun, either is <$10. Suction guns are sold next to grease guns, come with a 12” extension hose, and work well. Fill until lube barely runs out the fill hole. Clean the sealing surface around the fill plug hole with a rag. Install the fill plug and torque to 35 foot-pounds. Properly dispose of the old gear oil.

Materials:

2 drain plug gaskets, Toyota part no. 12157-10010 @ $.95 each from local dealer or $.69 from online discount dealer. Description: hollow aluminum crush type gasket with 18.2mm ID x 24.1mm OD x 2mm thick (prior to crushing).

1.8 quarts of SAE 80W-90 hypoid gear oil that meets or exceeds American Petroleum Institute (API) standard GL-5 (chose your own poison, e.g. petroleum based, synthetic, Redline, Amsoil, Castrol, Mobil, etc.).

Anti-seize compound

Tools:

Racket with 10mm Allen head socket (requires Allen socket to use torque wrench when installing plugs)
12mm socket and extension
Torque wrench
>1-gallon drain pan
Wire brush
4 ft. of ¼” ID clear plastic tubing or lube bottle pump or suction gun
Rags or paper towels
Disposable latex gloves (recommended)

Notes:

1. Verify plugs are 10mm Allen head; could be 24mm hex head or other size
2. Drain plug gaskets fit 10mm Allen head and 24mm hex head plugs
3. A Torx T-55 bit fits a 10mm Allen
4. If drain plugs are 24mm hex head, a racket with 15/16” six-point socket is recommended. 15/16” twelve-point or 24mm six or twelve-point should work. 15/16” six-point PTI-drive socket (relieved corners) is the safest bet because it grips the six sides, not the six corners.
5. Fill and drain plug threads are M18 x 1.5mm pitch.
6. Drain plug has magnet, fill plug does not
7. The Allen head plugs seem to be made from stronger steel than hex heads
Resurrecting this old thread. Confirming that the tilting up of the front end with the ramp is not enough to make a difference in making sure that the fluid level is correct when filling? I'm planning on changing the front diff fluid soon but neither my driveway or the street in front of the house is level. Normally this is not an issue for changing engine oil and etc. since I know how much to fill, but I read somewhere that the vehicle needs to be level for changing diff and t-case fluids since you fill it until it starts to drain from the fill hole, so I've been brainstorming on how to get my vehicle leveled properly on my inclined driveway. However, if the amount of tilting up such as the amount created by driving up onto the ramps does not really affect the accuracy of making sure that the fluid level is correct, then I'll stop trying to figure out ways to level my 100 on my driveway before changing my fluid. The incline of my driveway is probably similar to that amount of incline created by ramps.
 
Found several threads of folks using M1 75-90 GL-5 in their front diffs. I’m going for it, cheaper to buy it in the gallon for front/rear and transfer case
 
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Finally got the time to do the:

~~Front Diff~~
BB819EED-6CD6-474D-9EBD-C418F16DC89D.jpeg


~~Transfer Case~~
71A7136F-05BF-4867-B01E-2E8213CB0420.jpeg


~~Rear Differential~~
26AEAB50-75CB-4B09-BF5E-C8765801D300.jpeg


I cannot find any service records pertaining to a FD/TC/RD change fluid from the previous owners (you be the judge). I noticed the front diff oil and transfer case oil are really dark and smelled burnt, while the rear diff oil is brown in color. Also, I collected no metal shavings. Guessing I dodged a bullet here.

How our diff oils should be:
7907781C-E3C8-4C00-85AF-6B9761AC518C.jpeg


Posted it here, transfer case and rear diff oil change threads for everyone’s convenience.

28E44DC8-A36B-4302-A49D-9EF96AD3DD53.jpeg
 
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@OEMGUY0720 - interesting thanks for posting.

Can you confirm where you used M1 75W-90 (I assume front and rear diffs) vs. the RP (t-case?).

Thanks, gearing up to do this myself, hopefully this weekend, a little worried about what I am going to find...
 
@OEMGUY0720 - interesting thanks for posting.

Can you confirm where you used M1 75W-90 (I assume front and rear diffs) vs. the RP (t-case?).

Thanks, gearing up to do this myself, hopefully this weekend, a little worried about what I am going to find...

The Royal Purple went to the engine, the Mobil1 LS-rated gear oil went to the front diff, transfer case and rear diff
 
The Royal Purple went to the engine, the Mobil1 LS-rated gear oil went to the front diff, transfer case and rear diff

Can you chime in on how to know if our rigs have / need limited slip diff fluid ? I thought it would specify this with a tag on the rear diff, which mine doesn't appear to have on any of the gear boxes.
 
Can you chime in on how to know if our rigs have / need limited slip diff fluid ? I thought it would specify this with a tag on the rear diff, which mine doesn't appear to have on any of the gear boxes.
What year is your rig Mike? As far as I know (someone pls correct me if I’m wrong), you can use an LS-rated diff oil even if your differentials are open-types.

LS-rated diff/gear oils also is a requirement for air-operated, electronic-activated and eaton e-lockers (centripetal activated). On the other hand, if a non-LS diff oil is used in air, electronic and eaton type lockers it will produce a grinding sound on the third member.
 
Damn I have a bad habit of reading into things too much...

If I'm in a climate where we hit 0°F maybe once a year (North Carolina), I should run straight 90 weight in the diffs, right?

I keep watching people blow their diffs and cant help but to think its because everyone's throwing 75w-90 in them... 😅

*edit - been searching and apparently SAE 90 gear oil doesn't exist anymore. Closest synthetic I've found is AMSOIL 80w-90
 
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Haven’t read all the posts but you guys are using a garden sprayer to refill correct? It is by far the easiest and most efficient way to refill front rear and center diffs.
 
Haven’t read all the posts but you guys are using a garden sprayer to refill correct? It is by far the easiest and most efficient way to refill front rear and center diffs.
Dunno what a garden sprayer is , a fluid pump seems to be easy enough to get the fluid in there
 
Yes, zero mess and very efficient. Drain old oil then add same amount into pump to refill. That will keep pump very close to empty when ready for next oil change.

I have one pump for diff oils and one for tranny oil for the '04 and '06 sealed trannys.....which I rarely change.
 
Anyone know the Toyota suggested intervals for this change (How often or how many miles)?

I can't seem to find it anywhere.

Thanks
 
Anyone know the Toyota suggested intervals for this change (How often or how many miles)?

I can't seem to find it anywhere.

Thanks
I think every 50k miles (80k kms) is an acceptable interval.
 

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