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Transmission oil dilemma

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Hey guys,
I have finally gotten an overdrive installed on my 4-speed for my TR6 (J-type) and am awaiting its arrival from snowbound Connecticut. The problem is, I have always run Hypoy Gear Oil, GL-4, SAE80W90 in my transmission. Quantum Mechanics, who rebuilt the overdrive and installed it for me, insists that I only run 30WT non detergent oil in the unit now. This is contrary to what Triumph has said (my guru @ TRF, Dave). Of course the oil from the tranny and the overdrive are one and the same. What to do? Surely don't want to void any warranty on the new unit. Has anyone every heard of such contrary information before? Imput???

Bill
 
You may want to get the warranty for your transmission from the builder. Also, it might be worth asking them about using 85W90 instead of 30W non-detergent. I have a D type o/d behind my 4 speed GT6 and I am using 85W90 with no issues.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Bob Buxbaum:
...asking them about using 85W90 instead of 30W non-detergent...<hr></blockquote>

I'll bite -- is there much difference between the two?
 
I think the viscosity of transmission oil is measured differently than engine oil. 30 wt might be almost the same as 75/80 transmission oil.
 
Phil, Yes;

Gear oil viscosity is measured at 150 F vs. 210 F for motor oil. Therefore, 40 W motor oil is the same as 95 W gear oil, etc.
D

[ 02-02-2004: Message edited by: Dave Russell ]</p>
 
I also have a Quantummechanics Jtype in my GT6. Your warranty indicates 30 weight, non-detergent oil. John Esposito at Quantum recommended Wolf's Head. Two excellent reasons to use the ND oil.

The most postive part about this is that the ND Wolf's Head is cheap as dirt, about $1.10 per quart.

I think it's the first cheap thing I've encountered in my restoration.

Cheers!
 
Bill--I have a bit over 12,000 miles on my John Esposito A-type O/D using ND 30W motor oil. No problems, and I think John knows what he's recommending. Since there is no filtration system in the O/Ds, you don't want detergency; quite the opposite, you want the junk to settle out. Also, detergents would create a foaming issue within the system at the hydraulic pressures used.

Stick with the motor oil!

Rick O.
72 TR6
 
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