Vehicle is 99 Isuzu Rodeo 4x4 with limited slip rear end. Question on which weight differential is right for the summer temperatures in Maryland with temps up to 100 already. Rodeo shop manual calls for SAE 75w-90 to 59 degrees F; SAE 80w-90 to 86 degrees F and SAE 80w-140 in hotter temps. Truck used as daily commuter of 80 miles, and stop and go traffic. What weight would you advice to use; 80-140 feels too thick in my opinion.
Differential Oil for Rear End
- Thread starter AxleRod
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75W-140 would work, or you could order some Amsoil Severe Gear 75W-110 from either Pablo or Gary. That is an excellent gear oil.
If you want to just make a local parts store purchase, Mobil 1 75W-140 is very good and it has the LS additive in it.
If you want to just make a local parts store purchase, Mobil 1 75W-140 is very good and it has the LS additive in it.
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If you are not towing with this vehicle and want your best fuel economy, I would stay away from the 140 oils. Especially since it is mostly used for commuting. Those recommendations are probably "geared" towards non-synthetic oils. I would be inclined to use a quality 75W-90 synthetic that is formulated for limited slip. Mobil 1, amsoil, Schaeffers, Redline, Royal Purple are several that come to mind.
Going with a synthetic is a no-brainer for me since these axles rarely hold more than a few quarts and do not require constant service like engine oil. The synthetics or blends will hold up better (Viscosity and oxidation) in the heat and flow faster when it gets really cold. The thickest oil I would use in your app would be Amsoil 75W-110, which is right in the middle. RP Max Gear is also on the heavier end of the 90 grade.
A synthetic blend would be another good, but less expensive option, and can be found at most auto parts stores. Pick up a bottle of limited Slip additive while you are there-you will probably need to add some or all of it to eliminate LS clutch chatter on turns.
Going with a synthetic is a no-brainer for me since these axles rarely hold more than a few quarts and do not require constant service like engine oil. The synthetics or blends will hold up better (Viscosity and oxidation) in the heat and flow faster when it gets really cold. The thickest oil I would use in your app would be Amsoil 75W-110, which is right in the middle. RP Max Gear is also on the heavier end of the 90 grade.
A synthetic blend would be another good, but less expensive option, and can be found at most auto parts stores. Pick up a bottle of limited Slip additive while you are there-you will probably need to add some or all of it to eliminate LS clutch chatter on turns.
Originally Posted By: bmwtechguy
If you are not towing with this vehicle and want your best fuel economy, I would stay away from the 140 oils. Especially since it is mostly used for commuting. Those recommendations are probably "geared" towards non-synthetic oils. I would be inclined to use a quality 75W-90 synthetic that is formulated for limited slip. Mobil 1, amsoil, Schaeffers, Redline, Royal Purple are several that come to mind.
Going with a synthetic is a no-brainer for me since these axles rarely hold more than a few quarts and do not require constant service like engine oil. The synthetics or blends will hold up better (Viscosity and oxidation) in the heat and flow faster when it gets really cold. The thickest oil I would use in your app would be Amsoil 75W-110, which is right in the middle. RP Max Gear is also on the heavier end of the 90 grade.
X2
Royal Purple MaxGear 75W-90!
If you are not towing with this vehicle and want your best fuel economy, I would stay away from the 140 oils. Especially since it is mostly used for commuting. Those recommendations are probably "geared" towards non-synthetic oils. I would be inclined to use a quality 75W-90 synthetic that is formulated for limited slip. Mobil 1, amsoil, Schaeffers, Redline, Royal Purple are several that come to mind.
Going with a synthetic is a no-brainer for me since these axles rarely hold more than a few quarts and do not require constant service like engine oil. The synthetics or blends will hold up better (Viscosity and oxidation) in the heat and flow faster when it gets really cold. The thickest oil I would use in your app would be Amsoil 75W-110, which is right in the middle. RP Max Gear is also on the heavier end of the 90 grade.
X2
Royal Purple MaxGear 75W-90!
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