I’m in a bit of a conundrum and seeking advice on gear oil. I usually stick with 75W-90 for my truck, especially since I do a lot of towing. However, I recently came across a jug of 75W-140 and I’m wondering if it would be a suitable substitute?
Key Considerations:
Viscosity Differences: The main difference between the two is thickness. 75W-140 is thicker, which might provide better protection in certain conditions. But I’m concerned about differences in performance, especially under high temperatures.
Temperature Handling: Warm climates and heavy towing can put a strain on gear oil. I’ve read that thicker oils can handle heat better, but will it also cause any issues in cold starts?
Differentials: I’ve habitually used 75W-90 in my differential, but I’ve heard mixed opinions about switching to the thicker 75W-140. Could this lead to overheating or affect the diff performance?
Questions:
Has anyone made this switch? What were your results? Did you notice any performance changes?
What about compatibility? Are there any risks or possible drawbacks I should be aware of?
Is there any situation where using 75W-140 would be more beneficial? Like, should it be limited to extreme conditions, or is it safe in average driving?
I’d really appreciate any insights, personal experiences, or expert advice on this topic. Thanks!
The difference between 75W-140 and 75W-90 is significant. The ‘W’ stands for winter, indicating how the oil flows at lower temperatures. The higher the second number, the thicker the oil when warm. 75W-140 is thicker and might not perform well if your vehicle is designed for 75W-90.
Good question, paigecruz! Using a thicker oil than recommended can lead to issues such as increased wear, overheating, and fluid starvation in specific areas of the gear assembly. Stick with the manufacturer’s recommendation for the best results.
It’s always best to err on the side of caution, especially with gear oils. Thicker oils can create extra pressure, which may lead to leaks or failures.
Just because 75W-140 may work in some cases doesn’t mean it’s a good choice for every scenario. Reflect on your usual driving conditions and make an informed choice.
Using 75W-140 instead of 75W-90 can lead to increased gear wear in applications where lighter oil is specified. The higher viscosity may not flow as well, especially in cold temperatures.
In my experience, using 75W-140 in a compatible gearbox meant less noise, but I did notice it ran hotter. Keep an eye on the temperature if you go this route!
While 75W-140 might seem like a stronger option, be cautious. It could increase friction in some systems, possibly leading to premature failure if it’s not compatible.