Gear Vendors oil

[Black dawg]

I know several people that when they complained to gv about the harsh engagement with atf, were told by gv to use 80/90 to soften the shift.

 

[blackcloudf250]

I changed the oil on my gear vendors unit last week and tried to track down the gm part numbers listed in the Gear Vendors manual. The part number is a 75w-90 manual transmission oil/fluid for gm transmissions. After I found out that oil cost $39 a quart(yikes!!!) I decided to call Gear Vendors directly and find out if there was an alternative. They told me they recommended Lucas oil 75w-90 gear oil for my particular unit and had been for the past 5 years with no complaints. After changing the oil the unit shifts fine, the oil I drained was definitely a gear oil of similar viscosity. The overdrive I have is installed on an 86 f250 6.9 2wd with a T-18 4spd. I would recommend calling Gear Vendors directly for your application, I'm sure they know what fluid should be used for your respective application.

 

[hce]

I changed the oil on my gear vendors unit last week and tried to track down the gm part numbers listed in the Gear Vendors manual. The part number is a 75w-90 manual transmission oil/fluid for gm transmissions. After I found out that oil cost $39 a quart(yikes!!!) I decided to call Gear Vendors directly and find out if there was an alternative. They told me they recommended Lucas oil 75w-90 gear oil for my particular unit and had been for the past 5 years with no complaints. After changing the oil the unit shifts fine, the oil I drained was definitely a gear oil of similar viscosity. The overdrive I have is installed on an 86 f250 6.9 2wd with a T-18 4spd. I would recommend calling Gear Vendors directly for your application, I'm sure they know what fluid should be used for your respective application.

Thats great, I can get lucas at work, for way less then I can buy gm synchromesh.

 

[Agnem]

I use the same stuff Icanfixall posted. It's a clear mineral oil, used in part, in some GM transaxles. ATF could be used in an emergency, but the mineral oil is really nice stuff. Yes, it's expensive, but then so is the GV, and it's a lot cheaper than pulling your GV out and rebuilding it.

 

[jaluhn83]

Interesting. Wouldn't have thought they'd recommend gear oil, but for sure go with what they suggest.

My concern with gear oil would that it's much thicker, and much harder to pump. As a general rule, gear oil is used in splash lubricated gearboxes and a lighter oil is used in boxes that have pumps - trying to pump gear oil, especially when cold is not easy and stands a good chance of damaging the pump if it's not designed for that thick of oil. This is why is causes problems when used in 13-45/56 t-cases - too thick of oil overstresses that pump and causes it to spin. (mind you, they pumps do that even with atf eventually due to a bad design, but using gear oil is very bad)

 

[hce]

This is why is causes problems when used in 13-45/56 t-cases - too thick of oil overstresses that pump and causes it to spin. (mind you, they pumps do that even with atf eventually due to a bad design, but using gear oil is very bad)

At the time synthetics were not main stream, I wonder if the choice in lubrication would have been different if they were.

 

[Agnem]

If you saw the gear oil they were recommending, you'd know it's not the 80-90wt stuff your used to. It reminds me of extra ****** olive oil.

 

[hce]

I think this is still on topic http://www.bgprod.com/blendr/viscosity.html, although it is veering a bit.