60k service - diff and transfer case washers

[Swederson]

A question for those that have changed the differential and transfer case fluids themselves... I want to confirm the correct washers to use. From buying the parts at the local Toyota dealer, I was lead to believe the crush washers were for the front and rear differentials, both the drain and fill plugs (total of 4 washers). I also got 2 flat aluminum washers (0.080" thick) for the transfer case drain and fill plugs.

So, I've got the rear diff draining right now. The drain plug had a crush washer, and the fill plug had the flat aluminum washer. I checked the transfer case to compare, and the drain plug has the flat washer while the fill plug has a crush washer. Seems unusual. I haven't checked the front diff yet. (I have only had the LC for about 1k miles, and don't know if these fluids have been changed before. The PO probably didn't do it himself, but it may have been dealer serviced - and I kind of think they goofed up the washers.)

Unless I have overlooked it, the FSM doesn't appear to clearly specify where the crush or flat washer is used.

Can anyone confirm the proper washers for drain plug and fill plug for the differentials, as well as the transfer case? I plan to use the crush washers on the differentials (just like in the FAQ) unless anyone has a good reason not to. Thanks.

- Dean
2001 TLC

 

[spressomon]

A question for those that have changed the differential and transfer case fluids themselves... I want to confirm the correct washers to use. From buying the parts at the local Toyota dealer, I was lead to believe the crush washers were for the front and rear differentials, both the drain and fill plugs (total of 4 washers). I also got 2 flat aluminum washers (0.080" thick) for the transfer case drain and fill plugs.

So, I've got the rear diff draining right now. The drain plug had a crush washer, and the fill plug had the flat aluminum washer. I checked the transfer case to compare, and the drain plug has the flat washer while the fill plug has a crush washer. Seems unusual. I haven't checked the front diff yet. (I have only had the LC for about 1k miles, and don't know if these fluids have been changed before. The PO probably didn't do it himself, but it may have been dealer serviced - and I kind of think they goofed up the washers.)

Unless I have overlooked it, the FSM doesn't appear to clearly specify where the crush or flat washer is used.

Can anyone confirm the proper washers for drain plug and fill plug for the differentials, as well as the transfer case? I plan to use the crush washers on the differentials (just like in the FAQ) unless anyone has a good reason not to. Thanks.

- Dean
2001 TLC

I know I used the crush washers on both diffs...and I am fairly certain I used the same crush washer on the t-case. However I use the aluminum coated washer on the oil pan drain plug...

 

[NMuzj100]

I thought they were all the same.

Question along the same lines. Are all the OEM cruiser plugs magnetic ?

 

[9toys]

I just reused the old ones and they haven't leaked yet.

 

[KathmanduCruiser]

I thought they were all the same.

Question along the same lines. Are all the OEM cruiser plugs magnetic ?

I think, at least the diff and t-case drain plugs are magnetic, but not the fill plugs. I do not know about other plugs.

 

[Swederson]

Alright, thanks for your feedback. I checked with 3 different dealers (including CDan's) and the answer is: the front and rear diffs get the crush washer for both the drain and fill plugs. The transfer case is different - it gets the thick flat aluminum washer on the drain and fill plugs.

I've now redone mine so they are the way they are supposed to be (and pray for no leaks!).
- Dean

 

[KathmanduCruiser]

Alright, thanks for your feedback. I checked with 3 different dealers (including CDan's) and the answer is: the front and rear diffs get the crush washer for both the drain and fill plugs. The transfer case is different - it gets the thick flat aluminum washer on the drain and fill plugs.

I've now redone mine so they are the way they are supposed to be (and pray for no leaks!).
- Dean

The parts guy at the only local Toyota shop in town told me it is the same washers in both diffs and the TC. I should have known better than to take his word for it..... I used an aluminum crush washer in the TC. I hope it won't be a problem because I have no interest in doing the fluid exchange again anytime soon.

 

[Swederson]

If it's any consolation, my t-case fill plug had the crush washer - and no leaks.

Seems odd to have the 2 styles of washers on the same vehicle. The plugs and threads of the diffs and t-case are almost interchangeable. They are all vented to the atmosphere (no high pressure fluid). The gear lube is the same (techinically they are spec'd a little different, but in reality I bet most here use the same stuff). The thing I don't know is temperature or vibration of the gears inside - if that's the issue.

Or, maybe at Toyota, the Suspension and Axle division didn't talk with the Transfer Case division...

 

[TRFCSUX]

Hey Swederson, How much and what type of fluid did you use.It looks pretty easy but ive been putting it off? thanx

 

[KathmanduCruiser]

Hey Swederson, How much and what type of fluid did you use.It looks pretty easy but ive been putting it off? thanx

The question was for Swederson, but I felt like answering too since I recently tried doing mine too. My TC fluid exchange went very easy. On the rear diff, the fill plug opened easily, but I could not get the drain plug to open. On the front diff, I could not get the fill plug to open. I went with Mobil1 75w-90.

 

[Swederson]

Hey Swederson, How much and what type of fluid did you use.It looks pretty easy but ive been putting it off? thanx

As for gear lube, I bought 7 1-quart bottles of Mobil1 synthetic 75W-90. You'll have maybe a half quart left over. The diff and t-case fluids are spec'd a little different, but the 75W-90 basically covers them all. I did not get the Mobil version with the LS additive (in case you checked Mobil's website), just the normal synthetic gear lube.

A few other tidbits to add in...
From the FSM, the torque spec for the drain and fill plugs on the front and rear diffs is 36 ft lbs. For the t-case, it's 27 ft lbs. I had overlooked that clue when I originally questioned which washers go with which plugs.

For filling the t-case, I used a short length of vinyl tubing on the end of the quart bottle. Probably 8"-10" long. Don't go too small in diameter, as it takes a lot longer to squeeze the gear lube through. 1/4" ID or 5/16" ID, clear or translucent (so you can see the fluid flowing) is probably best (a hardware store item).

For filling the front diff, IIRC the FAQ suggests a 4' length of tubing and an assistant. I used about a 16" length and did it myself. Just pay attention that the end of your tube stays in the fill hole. Figure out where you want to hold the bottle when you are squeezing it before you cut the tubing.

On my '01, these 3 drain plugs have magnets. The fill plugs to not. Other model years are probably similar... Hope this helps someone down the line.

 

[Jim_Chow]

I just did mine 3 months ago, got the parts from CDan. The front/rear diffs both use the same gold-colored crush washers for the fill & drain plugs (this is the same crush washer used on the 4runner and other toyota trucks). The t-case uses these siler aluminum washers (non crush type) for both the drain & fill. If someone used a silver washer for your diff fill and crush for the drain, they did it wrong. Oil pan drain plug uses the black, composite washer. Hondas use aluminum oil drain pan washers, toyotas don't.

To fill, I got a 5 gal pail of Mobil delvac 1 75w90 gear oil w/ the pump. You just put the hook end of the pump hose in the fill hose, stand beside the car and pump until gear oil starts to ooze out. If you have AHC, make sure the AHC is in N mode when you top off the rear diff. Otherwise, the lift causes the rear axle to rotate forward so the fill bolt points more downward. This means if you have any lift (like a 2" lift and didn't compensate by using longer control arms), you are putting in LESS gear oil than the desired amount. Of course, the FSM says you just need to be within 0.5" of the fill hole, but I thought I'd just mention it.

 

[9toys]

Auto zone sells a cheap pump that screws into gallon containers that I used to fill my gearboxes. I did have to jack up the front end to get enough clearance to get to the top of the stroke on the front diff of my 99LC. Otherwise it worked fine. I re-used the original washers and they work fine. Along that line, if the washer on my oil pan ever got changed in 107K miles on my 2000 Tundra, it was the few times the dealer changed the oil, because I never changed it. i changed the oil every 3-4K miles and never had a leak.

 

[TRFCSUX]

Thanx

Very helpful as always,you guys are great!

 

[uHu]

Went to the Toy.dealer asking for washers for all the drain & fill plugs. Got 6 equal grey washers + a fiber washer for the engine oil.
They have all worked OK. Had a bit of leak on the rear's fill plug before, when using old washer.
fwiw

 

[Swederson]

Jim_Chow and 9toys - Having a pump would certainly make things go a little quicker on the filling. It's good to include these comments to give other MUD folks ideas/shortcuts. For me, I don't go through enough gear lube to buy it in multi-gallon containers. When I change it again (in 30k) I'll get it from the store, where it will probably be fresher than if it sat in my garage for a couple years.

Jim_Chow - I have read in a number of your posts about using the "Delvac" version of Mobil products. I thought "Delvac" was only associated with Mobil's engine oils made for diesels. I think the additives are a little different than in Mobil1 for gasoline engines. IIRC, maybe that's why you are able to get 19mpg sometimes???

 

[Jim_Chow]

Jim_Chow - I have read in a number of your posts about using the "Delvac" version of Mobil products. I thought "Delvac" was only associated with Mobil's engine oils made for diesels. I think the additives are a little different than in Mobil1 for gasoline engines. IIRC, maybe that's why you are able to get 19mpg sometimes???

FWIW, from the descriptions, it sounds like the M1 Delvac 75w90 gear oil is for heavy-duty applications (heavy trucks, mining/agriculture/construction equipment where you are carrying heavy loads, gears are under lots of pressure) while the normal M1 75w90 is for autos/light trucks and mild EP apps. Here are the specs:

http://www.imperialoil.ca/Canada-English/Files/Products_Lubes/IOCAENCVLMOMobil_Delvac_Syn_GO.pdf

http://www.mobil.com/Canada-English/Lubes/PDS/IOCAENPVLMOMobil_1_Synthetic_Gear_Lubricant.asp

For engine oils, the additives for the diesel are different than oil for gas engines. Anyone correct me if I'm wrong, but I believe the diesel engine oils have more phosphorus and/or zinc, which supposedly reduces valve train wear compared to the gasoline engine oil, plus more additives to soak up the (diesel) combustion byproducts. The drawback is more potential (?) damage to catalytic converters. If you look at the spec sheets for M1 delvac 5w40, the TBN (total base number or measure of additives) is 12 while the TBN for the M1 gasoline engine oils is less. Ash levels are also similar.

As for fuel economy, I've yet to run the 0w40 in the LX, but have gotten similar economy numbers in my honda running 0w40 vs. Delvac 1 (both about 5-10% better than M1 10w30 and dino). If it matters to you, the 0w40 is cheaper than the Delvac 1 5w40...like $24/gal vs. $28/gal. The fuel economy thing depends on lots of factors. Besides the fluids, I push the cross bars on the roof rack to the rear, use Chevron 91 gas (get 10% better mpg than chevron 87), and probably most importantly, set the cruise control to 70mph!! (2200-2400 rpm) Oh, maybe having the 5spd tranny helps over the 4 speed?

As far as not using enough gear oil to use multi-gallon containers, just buy another Toyota 4x4!

 

[KathmanduCruiser]

The fuel economy thing depends on lots of factors. Besides the fluids, I push the cross bars on the roof rack to the rear

Does that make any difference?

 

[Jim_Chow]

Does that make any difference?

In theory, the airflow in the front of the vehicle is more laminar while that in the rear is more turbulent. So the idea is to hide the cross bars in the turbulent flow as much as possible (or better yet, remove them...the less stuff on the roof, the better the aerodynamics). Other people on clublexus claim it reduces noise, which somewhat confirms the theory in a qualitative way (in the same way that installing a windshield moulding incorrectly will create wind noise). For the same reason, if you put one of those cool-looking safari-style racks on your roof, your fuel economy will tank big-time on the interstate due to the additional wind resistance (plus more noise from disrupted aerodynamics). Remember, wind resistance increases approximately with the velocity squared.

 

[uHu]

In theory, the airflow in the front of the vehicle is more laminar while that in the rear is more turbulent. So the idea is to hide the cross bars in the turbulent flow as much as possible (or better yet, remove them...the less stuff on the roof, the better the aerodynamics). Other people on clublexus claim it reduces noise, which somewhat confirms the theory in a qualitative way (in the same way that installing a windshield moulding incorrectly will create wind noise). For the same reason, if you put one of those cool-looking safari-style racks on your roof, your fuel economy will tank big-time on the interstate due to the additional wind resistance (plus more noise from disrupted aerodynamics). Remember, wind resistance increases approximately with the velocity squared.

It certainly improves both mpg & noise to remove the crossbars. They make a rumbling kind of noise, coudn't understand what was wrong the first time I put them on....

About moving the crossbars to the rear:
AFAIK, and have seen on illustrations from wind tunnel testing, there is more turbulence at the front of the roof, but mainly in front of the roof rails (or at the front end of). The air comes up along the windscreen, and makes turbulence just behind it, and then decreases on it's way rearwards as it gets closer to the roof again.
There is more turbulence at the very back, yes, but that's behind the vehicle.

Otherwise I agree fully with Jim about generally more turbulent towards the rear, only making an exeption for a long, flat (not curved) roof, like on the LC100.