Differential oil change procedure

[itwonder]

I have note been able to find the procedure for changing the front and rear differential oil. Is there one, or is it just so obvious one is not needed?

[DevinSixtySeven]

grunt ugh! ug ug, grunt! lucky for you, i did this last night .

...get a 24mm socket and a breaker bar. attack the rear fill plug first (never go for the drain plug first, if it comes out and not the fill, yer up a certain creek), once it's out, attack the drain plug. clean both plugs (they both contain a magnet), replace drain plug (torque to 39ft#), add ~3L oil (add until it just barely dribbles out the hole), replace fill plug (39ft#). while you're at it, extend the rear diff breather up to the engine compartment, it's good for your immortal soul, or at least for the rear diff.

now grab a 10mm hex key on a 3/8" drive, a socket wrench and a breaker bar. drop the front skid plate so you can jump the front diff, and break loose the fill plug, its in front. if it doesn't come out at once, curse at it, and it'll come clean. make sure to bang your knuckles a few times on the crossmembers and engine block--gloves are handy here, 'specially the real snug 'mechanix' gloves. once that's out, remove the drain plug, it faces the driver's side. clean plugs, replace drain (48ft#), pump 1.15L fluid in to front diff using a fi-dollah diff lube pump from napautoboys or wherever, stop when a little bit dribbles out, replace fill plug (29ft#), clean up dribbles, move to t-case.

t-case plugs are both at back of case, remove fill, then drain, clean and replace drain (27ft#), fill w/1L fluid, replace fill plug (27ft#), clean and degrease everything, replace skid plate if you had to drop it to do the front diff.

now kick your feet up and have a beer.

-sean with a shop manual

[KDTundra]

Wow, was this timely! I'm in the process of getting this done also. Was wanting to go synthetic and had a quick question:

The front diff and transfer case both call for GL-5 SAE 75w-90 gear oil 1.2 qts and 1.1 qts respectively). The rear diff calls for GL-5 SAE 90 only (3.7qts). Mobil 1 makes the GL-5 SAE 75w-90 but not the single viscosity SAE 90. Any suggestions on the synthetic version for the rear diff? Is the 75w-90 compatible with the rear diff? Thanks.

KDTundra

Originally Posted by DeepStealth

grunt ugh! ug ug, grunt! lucky for you, i did this last night .

...get a 24mm socket and a breaker bar. attack the rear fill plug first (never go for the drain plug first, if it comes out and not the fill, yer up a certain creek), once it's out, attack the drain plug. clean both plugs (they both contain a magnet), replace drain plug (torque to 39ft#), add ~3L oil (add until it just barely dribbles out the hole), replace fill plug (39ft#). while you're at it, extend the rear diff breather up to the engine compartment, it's good for your immortal soul, or at least for the rear diff.

now grab a 10mm hex key on a 3/8" drive, a socket wrench and a breaker bar. drop the front skid plate so you can jump the front diff, and break loose the fill plug, its in front. if it doesn't come out at once, curse at it, and it'll come clean. make sure to bang your knuckles a few times on the crossmembers and engine block--gloves are handy here, 'specially the real snug 'mechanix' gloves. once that's out, remove the drain plug, it faces the driver's side. clean plugs, replace drain (48ft#), pump 1.15L fluid in to front diff using a fi-dollah diff lube pump from napautoboys or wherever, stop when a little bit dribbles out, replace fill plug (29ft#), clean up dribbles, move to t-case.

t-case plugs are both at back of case, remove fill, then drain, clean and replace drain (27ft#), fill w/1L fluid, replace fill plug (27ft#), clean and degrease everything, replace skid plate if you had to drop it to do the front diff.

now kick your feet up and have a beer.

-sean with a shop manual

[Buzzard]

I used Mobil1. One suggestion--The drain plug is off center and a little higher than the low point of the rear end. When you pull the drain plug jack up the driver side of the truck rearend a little to get a complete drain. Lower when you fill. Also I didnt have a 24mm socket --a 15/16 will work. --Buzz

[DevinSixtySeven]

the synth mobil-1 75w90 will do fine throughout the diffs.

[KDTundra]

Just the info I needed. Thanks Buzzard and DeepStealth.

KDTundra

[HotRod8]

I also would like to switch over to synthetics in my diffs and transfer case and I have a couple of questions.

1. Do any of the drain or fill plugs have gaskets that need to be replaced? I know my previous Toyota had "crush" gaskets on all the drain and fill plugs on both diffs, the transfer case and the transmission.

2. What type/brand of LSD additive (friction modifier) are you guys using in the factory LSD?

Thanks,
Rod

[Verndog]

Originally Posted by HotRod8

I also would like to switch over to synthetics in my diffs and transfer case and I have a couple of questions.

1. Do any of the drain or fill plugs have gaskets that need to be replaced? I know my previous Toyota had "crush" gaskets on all the drain and fill plugs on both diffs, the transfer case and the transmission.

2. What type/brand of LSD additive (friction modifier) are you guys using in the factory LSD?

Thanks,
Rod

I'm going to be doing this soon myself. I picked this up in a LSD thread a while back.

Limited slip rear diff uses : Hypoid gear oil for limited slip differentials API GL-5

Kevin

[DW]

Being as I'm educated beyond my intelligence (Masters + 30 hours), I have to research everything. Since Toyota calls for 90 WT, in the rear end (and since Mobil 1 75W-90 is on the 'light side' of 90 weight) I looked on the various synthetic oil spec. sheets and found Royal Purple to be closest in the 40*C & 100*C temp. ranges in viscosity to a good, strong 90 Weight, I'm going with Royal Purple (75W-90) in the rear end plus the GM friction modifier (2 oz, as the RP already had friction modifier properties in it. However, I went with Mobil 1 in the front axle and the transfer case, as I sure do like the service I've gotten from Mobil 1 engine oils over past years and run it it all my vehicle engines. I'm sticking with the T-IV in the transmission, until someone comes up with a syn. transmission oil that meets (not merely 'recommended' for use in) T-IV specifications...and I surely do hope that maker is Mobil 1! I didn't change out the 'crush gaskets this time as this was the 1st drain & refill on all axles & transfer case @ 15,000 on the 03 4WD Tundra. BTW, the front diff. drain magnet on mine had about an eighth teaspoon of gunk similiar to the grey stuff usually found in A/T oil pans atached to the plug and the 'color' of the fluid wasn't nearly so nice and golden as the fluid coming out of the transfer case. I am going to change front axle fluid every 15,000 as I believe that barely over a Liter capacity to be marginal in, even when using a good synthetic.

Originally Posted by HotRod8

I also would like to switch over to synthetics in my diffs and transfer case and I have a couple of questions.

1. Do any of the drain or fill plugs have gaskets that need to be replaced? I know my previous Toyota had "crush" gaskets on all the drain and fill plugs on both diffs, the transfer case and the transmission.

2. What type/brand of LSD additive (friction modifier) are you guys using in the factory LSD?

Thanks,
Rod

[HotRod8]

I'm going to be doing this soon myself. I picked this up in a LSD thread a while back.

Limited slip rear diff uses : Hypoid gear oil for limited slip differentials API GL-5

Kevin

Yes; I know that, it's right in the owner's manual. But, if I recall correctly a few members have still needed to add the friction modifier to quiet the chattering of the LSD clutches, correct me if I'm wrong. I suppose it may depend on the type of synthetic gear oil being used (they seem to all claim compatibility with LSD units).

Now I'm really confused.....

I didn't change out the 'crush gaskets this time as this was the 1st drain & refill on all axles & transfer case @ 15,000 on the 03 4WD Tundra.

nope, they use a reusable metal washer-style gasket.

The crush gaskets I'm referring to are a metal washer-style gasket that "crush down" when correctly torqued. They are not, theoretically re-usable, at least not according to the factory service manual (for my old truck). On my old truck, I did re-use them, every second oil change. As this one's still under warranty I will replace them, if in fact it actually has them. The only reason I ask is that I like to have this kind of thing on hand before starting the job, rather than wait until the oil is in the drain pan and have to go drive to the dealer, in my case about a 50 mile round trip. From your post DW, I beleive that there are "crush" gaskets on the drain and fill plugs; I'm sure the dealer will be able to confirm.
As far as the LSD additive after some further research it seems that you don't want to add this stuff unless actually required. I suppose one could add it later if there is indeed noise from the LSD.


Thanks,
Rod

[DW]

Rod: I goofed up. The other post was correct on the drain/fill plug washers. They ain't crush washers, of at least they wern't on my 03 4wd Tundra V-8. And I, too, have read somewhere that you don't need to add friction modifier to the rear anti-slip unless the synthetic doesn't have enough in it to keep from chattering. But, being old and lazy, I didn't want to get back under the pickup, so I compromised and added 2 oz. on the GM additive rather than the 4 oz. called for if you used the GL-5 for non-slip differentials. Then I did the figure 8's out in the pasture at my place and I'm not getting any noise, so I figure all is well.
Good luck on your maintenance.

[ricqik]

What could/would happen if none of the fluids were changed for 85k?

Cuz I thinks it about time to do mine, only after I started hearing what sounds like swishing and hissing like sound from the rear area.

[DevinSixtySeven]

rod, it's a very thin stainless washer...i've never changed mine, ever.

ricqik, change it yesterday. there was a lot of gunk in there when i changed mine at 30K, less so at 60K, mostly golden at 90k. you may need a breaker bar to get the fill plug off (always the fill plug first !), and the fluid will probably be pretty nasty. take care of it asap .

-sean