 |
|
|
1979-1993 & 94 Conv [Subscribe to Daily Digest] |
I've got the maintenance records back to the purchase of the car (I'm only the 3rd owner). Conventional 75 wt gear oil is all that was ever used prior to the 5th gear problems it developed (see my original post from a year ago; it's linked at the start of this thread). That's when the problem was "corrected" by cleaning it out with solvent & motor oil flushes, & then giving it ultra-premium syn gear oil. But alas, the 5th gear problem came back, even with an unintentional short interval thrown in for good measure. I'm glad your gear oil is working for you. I'm not trying to convince you to change to something else. If my 75 wt & BG MGC was still working for me, I never would've started looking for anything else. But it wasn't working, & neither was the $15/qt fully synthetic BG Syncro Shift II.
Actually, EP additives are put in gear oils precisely BECAUSE the oil gets squeezed out from between the gears (there's no way that EP additives can ever "prevent the oil from getting squeezed out"). This is your last line of defense in lubrication protection (maintaining an oil film provides your primary (& best) protection). Getting a more durable oil in there will prevent particles from being generated in the first place. That's why I chose the better film strength of a synthetic 40 wt motor oil. Gear oil viscosities are measured at lower temps than engine oil viscosities, so my 40 wt is comparable to the vis of an 85 wt gear oil, whereas a 75 wt is comparable to only a 20 wt motor oil. I also feel the increased level of anti-wear additives found in diesel-style oils are a good thing, so that's why I chose a dual-rated (gasoline/diesel) oil over a gasoline-only oil.
I've also heard (but can't verify) that the additives in gear oils don't hold up well in high operating temps. This makes sense to me, since most gear oils are designed with in-line drivetrains in mind, & those trannies see lower temps than our tranny-as-engine-heatsinks do. Since motor oils are designed to operate in combustion temps, I know they'll survive in our trannies.
posted by 209.247.22...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
