My 1982 Moto Guzzi specifies straight 90 weight for the gearbox and final drive. I am leaning towards the Amsoil 80w-90 gear oil for both. I don't want to just assume that this multi weight is fine. Opinions and recommendations are welcome. Also, the manual also suggests .75 oz of a moly additive for the final drive. Do newer oils give sufficient protection or should I keep adding the moly?
Straight 90 weight specified for mcy. Suggestions?
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80W-90 basically is a straight weight that is made from better base stocks, if I remember right. It is similar to a straight 40 motor oil vor viscosity characteristics.
Some Schaeffers gear oils already have moly in them. I don't think they make a SAE 90 anymore, but maybe an 80W-90. Check with salesrep (site sponsor).
Originally Posted By: MGregoir
80W-90 basically is a straight weight that is made from better base stocks, if I remember right. It is similar to a straight 40 motor oil vor viscosity characteristics.
If this is correct I am confused. An 80W-90 with the same viscosity as a straigh 40w? Can someone expand on this? The gear lubes that I have used in the past seemed to be much heavier/thicker than straight 40 weight. Maybe I find an old fashoned 90 and hope for the best with annual change outs.
80W-90 basically is a straight weight that is made from better base stocks, if I remember right. It is similar to a straight 40 motor oil vor viscosity characteristics.
If this is correct I am confused. An 80W-90 with the same viscosity as a straigh 40w? Can someone expand on this? The gear lubes that I have used in the past seemed to be much heavier/thicker than straight 40 weight. Maybe I find an old fashoned 90 and hope for the best with annual change outs.
Originally Posted By: INDYMAC
Some Schaeffers gear oils already have moly in them. I don't think they make a SAE 90 anymore, but maybe an 80W-90. Check with salesrep (site sponsor).
Thanks! I checked them first and the moly lubes only come in 5 gal pails. Way too much for my appliction.
Some Schaeffers gear oils already have moly in them. I don't think they make a SAE 90 anymore, but maybe an 80W-90. Check with salesrep (site sponsor).
Thanks! I checked them first and the moly lubes only come in 5 gal pails. Way too much for my appliction.
SAE has a gear oil and a motor oil viscosity.
I would worry more about a multi-grade like a 75W-140 than 80W-90.
75W-90 gear oil is quite comparable to 10W-40 motor oil for viscosity characteristics but not performance as they are blended to do different things with different additives
80W-90 gear oil is basically a straight grade, I would think.
Belray makes a straight 90, and you can get Hypoid 90 Lower Unit lube rated MT-1 and GL-5 from a lot of marine shops as well. It comes in ten ounce containers for about $4 a piece. Whatever you get, look for something that passes J2360 or MIL-PRF-2105E specifications and is a 75W-90, 80W-90 or straight 90, I would think.
I would worry more about a multi-grade like a 75W-140 than 80W-90.
75W-90 gear oil is quite comparable to 10W-40 motor oil for viscosity characteristics but not performance as they are blended to do different things with different additives
80W-90 gear oil is basically a straight grade, I would think.
Belray makes a straight 90, and you can get Hypoid 90 Lower Unit lube rated MT-1 and GL-5 from a lot of marine shops as well. It comes in ten ounce containers for about $4 a piece. Whatever you get, look for something that passes J2360 or MIL-PRF-2105E specifications and is a 75W-90, 80W-90 or straight 90, I would think.
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It's all about temperature.
A 75-90 is thicker when cold than hot. Why go even thicker than that when cold?
25+ years have seen improvements in oils/lubes, but this goes beyond that.
A 75-90 is thicker when cold than hot. Why go even thicker than that when cold?
25+ years have seen improvements in oils/lubes, but this goes beyond that.
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Look up Schaeffers oil for the final drive they have gear oils with moly in it. There is a site sponser that can help you ,as well as an Amsoil sponser .
Gary-
Thanks for the chart! That really helps. What Amsoil product would you recommend for my application? Is the 80w90 more suitable that the 75w? TIA
Unfortunately Schaffer's only sells their moly lube in 5 gal pails. I only need a quart or two.
Thanks for the chart! That really helps. What Amsoil product would you recommend for my application? Is the 80w90 more suitable that the 75w? TIA
Unfortunately Schaffer's only sells their moly lube in 5 gal pails. I only need a quart or two.
How about adding Liqui-Moly MoS2 antifriction for gears?
http://store.interautopartssd.com/mos-2-antifriction-for-gears-p-30.html
http://store.interautopartssd.com/mos-2-antifriction-for-gears-p-30.html
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