Amsoil 80w90 severe gear vs 75w90 long life synthetic? For light duty truck use

Joined
May 23, 2018
Messages
68
Location
Philippines
Hey there, as I've said in the topic I just need a quick advice. My truck is an 2017 mdl Isuzu Dmax 3.0L m/t 4x2, no lsd. I'm nearing my rear diff oil change interval and I usually use this truck to haul 200-300kg boxes of coffee once or twice a week and a regular (unloaded) commuter every other day. Which oil should suit me the best?

This truck's manual just recommends GL-5 diff oil and other recommended fluids have GL5/MT-1 specs. I'm also in a tropical region so I guess the winter ratings don't make much sense here, so I'm open to recommendations (like even straight 90 with proper reasoning).
 
Last edited:
Either will serve you well and since you are in the Philippines and cold temperatures are not an issue, the 80W-90 will save you a few dollars.
Thanks for chipping in. I was wondering if what I'm doing qualifies for severe gear usage. Or will I just be served well by the long life synthetic (since by designation I'm able to run this oil for longer than the severe gear).
 
Thanks for chipping in. I was wondering if what I'm doing qualifies for severe gear usage. Or will I just be served well by the long life synthetic (since by designation I'm able to run this oil for longer than the severe gear).
I would not think that a 660 pound load in your truck would qualify for severe duty. With that said, the cost difference between the two is less than $5.00. If you wanted to add more protection, you could up the viscosity to 75W-110 which is the viscosity the upper range of 75W-90 used to be before the J306 tables were updated.
 
I actually did some backreading of SVG vs FGR in different forums. Severe gear is meant for consumer grade cars with lower capacity diff sumps, which were more prone to higher heat and FGR was meant for commercial big rigs with huge sumps where temps weren't much of a concern. Just posting it here for confirmation or correction if its actually incorrect.
 
The 80W90 has a bit higher viscosity than 75W90 at 40 degrees C. Same viscosity at 100 degree C.
I would use the 80W90...
 
Back
Top