API GL-5
Designates the type of service characteristic of
gears, particularly hypoids in automotive axles
operated under high-speed and/or low-speed, hightorque
conditions. Lubricants qualified under U.S.
Military Specification MIL-L-2105D (formerly MILL-
2105C) satisfy the requirements of the API GL-5
designation.
1986 to 1996 Manual Transmission and Transfer case use API GL4 or GL4 and GL5 80W90 or 75W90. Differentials use API GL-5 SAE 75W-90 or 80W-90 lubricant. Do not put a GL5 gear oil in the transmission unless it says GL4 and GL5. GL5 will attack the syncros.
Yes. Jeep does recommend 75w140 synthetic if used for towing.
GL5 or 6
GL4, or if GL5 must also say on the bottle safe for syncromesh or manual transmissions. GL4 is for tranny GL5 is for axles. this is in the operators guide in the glove box.
GL5 75W90 or 80W90 gear oil.
The 04 requires a 75/90 Synthetic and the 96 users an 80/90 GL5. Using 80/90 GL5 on gears that require synthetic lubricants will ruin them. Your answer is no. Iron
standards transmission oil you can try gL5 ...
GL5 80/90 gear lube
vauhall gear oil gl4 NOT gl5
75w-90 GL5 gear oil
Yes, You can. But quality of the mixture will be equal to the quality of the GL4 gear oil.
BMW recommends ONLY using BMW oil that can be purchased at their dealerships for their motorcycles, including the 1987 K75. For the transmission, you can use 1 Quart Mobil-1 GL5-75/90 or Castrol SAF-XO GL5-75/90 Synthetic Gear Oil.