Gear Oils for a FJ Cruiser

[Nick1994]

This is for my dad's 2007 Toyota FJ Cruiser 4x4 with the 6-speed manual transmission. It's a full time 4x4 and has around 115k miles. Has the factory electronic rear locker.

It's got all original fluids in it except the engine oil, and I mean everything is original. Time for a fluid change!

Below here I've got all the fluid specs from the Owner's Manual. Need some help with differential oils. This is AZ so no worries about being below 0 degrees. It specs SAE90 gear oil for temps above 0 and 75w90 for cold temps, but can 75w90 be used year round? Any recommendations?

Thanks for the help guys.

Transmission:
1.9qts GL4 or GL5 75w90

Transfercase:
1.5qts Hypoid GL5 75w90

Front Diff:
1.5qts Hypoid GL5 SAE90

Rear Diff:
3.1qts Hypoid GL5 SAE90

Differential Fluid Specs:
Recommended oil viscosity: Front
Full−time four−wheel drive models Above −18_C (0_F)
SAE 90
Below −18_C (0_F)
SAE 80W or 80W−90

Rear

Above −18_C (0_F)
SAE 90
Below −18_C (0_F)
SAE 80W or 80W−90

 

[DrRoughneck]

Mobil Delvac 1 GL5 75W90 synthetic all around.

 

[Nick1994]

So it doesn't need to say "hypoid" on the bottle?

 

[DrRoughneck]

All rear differentials (since the 1920s) use hypoid gears. GL5 is a formal API spec for hypoid gears: https://en.wikipedia.org/wiki/Gear_oil

 

[clinebarger]

Originally Posted By: Nick1994
So it doesn't need to say "hypoid" on the bottle?


GL5 means it IS a hypoid gear oil.

 

[02SE]

I have basically the same drivetrain in a different Toyota. For the first several years I used Mobil 1 75w90 in everything. Then I switched to Redline 75w90 in the front diff, rear axle, transfer case, and MT90 in the transmission. I always had just the slightest notchiness in the transmission. Last summer I had decided to pull the transmission and rebuild it due to suspected worn synchro's, but decided on a whim to first try Amsoil MTG in the transmission. To my surprise the slight notchiness disappeared..

 

[dlundblad]

Originally Posted By: DrRoughneck
Mobil Delvac 1 GL5 75W90 synthetic all around.


Would GL-5 be safe in the transmission?

 

[Hootbro]

For the last 7+ years, I have been running SuperTech 80W-90 gear oil in my FJ diff's with no issue. Winters are somewhat mild where I live with maybe at most a few weeks of sub 20F degree days.

Toyota changed the gear oil spec on the FJ's after the first couple of years calling out a 90 weight to a 75W-85 weight oil because some Canadian sold FJ's were grenading diff's and the move to a full synthetic 75W-85 was the fix. Being in AZ, you can get by using and GL-5 75W-90 or 80W-90 and be fine

 

[BrocLuno]

Originally Posted By: 02SE
I have basically the same drivetrain in a different Toyota. For the first several years I used Mobil 1 75w90 in everything. Then I switched to Redline 75w90 in the front diff, rear axle, transfer case, and MT90 in the transmission. I always had just the slightest notchiness in the transmission. Last summer I had decided to pull the transmission and rebuild it due to suspected worn synchro's, but decided on a whim to first try Amsoil MTG in the transmission. To my surprise the slight notchiness disappeared..


I would run Redline MTL (similar to the Amsoil) in any manual transmission that did not require ATF ... Silkier smoother shifts are the norm. It'll hold up to endurance racing conditions and you can run it for at least as long as the factory fill.

BTW - I sold a older Ford F-100 6 banger with a granny 4-speed that had well over 400,000 miles (three engines - they push out the center main with 11" HD clutch...) and it still had teh factory fill in the tranny. Never a lick of trouble and no need to change it. You think big rigs go around changing their tranny's or rear ends how often ...

 

[DrRoughneck]

Originally Posted By: Hootbro

Toyota changed the gear oil spec on the FJ's after the first couple of years calling out a 90 weight to a 75W-85 weight oil because some Canadian sold FJ's were grenading diff's and the move to a full synthetic 75W-85 was the fix.

I'm surprised a shift from W90 to W85 would make a difference. Got a link to these "grenading diffs"?

 

[DrRoughneck]

Originally Posted By: BrocLuno
You think big rigs go around changing their tranny's or rear ends how often ...

Freightliner has a 500,000 change interval on tranny fluid. They up it to 750,000 if you fill with Mobil Delvac 1.

 

[02SE]

Originally Posted By: BrocLuno
Originally Posted By: 02SE
I have basically the same drivetrain in a different Toyota. For the first several years I used Mobil 1 75w90 in everything. Then I switched to Redline 75w90 in the front diff, rear axle, transfer case, and MT90 in the transmission. I always had just the slightest notchiness in the transmission. Last summer I had decided to pull the transmission and rebuild it due to suspected worn synchro's, but decided on a whim to first try Amsoil MTG in the transmission. To my surprise the slight notchiness disappeared..


I would run Redline MTL (similar to the Amsoil) in any manual transmission that did not require ATF ... Silkier smoother shifts are the norm. It'll hold up to endurance racing conditions and you can run it for at least as long as the factory fill.

BTW - I sold a older Ford F-100 6 banger with a granny 4-speed that had well over 400,000 miles (three engines - they push out the center main with 11" HD clutch...) and it still had teh factory fill in the tranny. Never a lick of trouble and no need to change it. You think big rigs go around changing their tranny's or rear ends how often ...


I tried the Redline MTL, too.

I use Redline products in some extreme use scenarios. I generally find them to be exceptional. But in this instance the Amsoil MTG worked better in my transmission.

I never said anything about Class 8 trucks..

 

[Hootbro]

Originally Posted By: DrRoughneck

I'm surprised a shift from W90 to W85 would make a difference. Got a link to these "grenading diffs"?


Actually it is a change to the winter weight of 75W (75W-85) from a straight 90 weight. So about a 15 weight different. This also meant going from a conventional gear oil to a synthetic for better flow.

Toyota Canada issued a TSB "CAN-TSB2929" in October 07 followed by the USA TSB in November 07 discussing the fluid spec change. Word on one FJ forums at the time I remember reading was because of the first model year FJ's and the straight weight 90 was not cutting the super cold of Canada. My search foo sucks if you want a reference for that so believe me or not believe me, I could care less but it makes sense for the weight change on the differential gear weights after 2007.

https://www.toyotaparts.metro-toyota.com..._T-DL07-003.pdf

 

[MaximaGuy]

Amsoil 75W110 all the way for gear fluids and Toyota ATF all the way

 

[DrRoughneck]

Originally Posted By: Hootbro
Originally Posted By: DrRoughneck

I'm surprised a shift from W90 to W85 would make a difference. Got a link to these "grenading diffs"?


Actually it is a change to the winter weight of 75W (75W-85) from a straight 90 weight. So about a 15 weight different. This also meant going from a conventional gear oil to a synthetic for better flow.

Toyota Canada issued a TSB "CAN-TSB2929" in October 07 followed by the USA TSB in November 07 discussing the fluid spec change. Word on one FJ forums at the time I remember reading was because of the first model year FJ's and the straight weight 90 was not cutting the super cold of Canada. My search foo sucks if you want a reference for that so believe me or not believe me, I could care less but it makes sense for the weight change on the differential gear weights after 2007.

https://www.toyotaparts.metro-toyota.com..._T-DL07-003.pdf


Thanks.