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Discussion Starter #1
Yes another oil thread but I am all about finding parts and fluids that are readily available and thus inexpensive. Though when it comes to transmission oil for the nv4500 you must use this magical oil that is no longer produced or use an alternative oil that has to be shipped or go to a dealership so we don't destroy our transmissions. Well I can see why the fear mongering works here, because it's an expensive transmission and rebuilding it is probably not everyones ideal weekend activity... also you won't be changing the oil very often. But there has to be an oil that meets or exceeds the oem specs and available at auto parts stores or walmart. Recently there is someone on another forum that uses Mobil Delvac Synthetic Trans Fluid 50w mobil.com/english-US/Commercial-Vehicle-Lube/pds/NAXXMobil-Delvac-Synthetic-Transmission-Fluid-50. It meets and exceeds the oem specs, shouldn't harm the carbon fiber syncros and is readily available. The only concern I would have is the temperature between the gears. Does anyone have experience with this lube?
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Yes but are there any that I can go and pick up besides the dealership.
How should I know whats available where you live. Look for any 75W85 GL-4 Synthetic Gear Oil.
 

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Discussion Starter #5
Forgot to say thanks for the links by the way. So I was reading the links and it seems like some of them are saying that any gl-4 75w85 would work but then one article which the guy tested the mobil synthetic 5w30 Motor Oil for 5 years 40,000 miles ended up with premature syncro failure. But he suggested Royal Purple Synchromax or Pennzoil Synchromesh with no update on those trials. Those are available... but dont not recommend 75w85, rp says 75w90.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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In the Allpar article:
"Please note that 5w30 motor oil is not a far cry from 75w85 gear oil. In fact, 10w40 is about the same consistency (under thermal stress) as 75w90 gear oil. The numbers may seem far off, but they are much closer than many may realize."

I wouldn't be concerned about whether to use 75w85 or 75w90 as long at the oil meets GL-4 specs.
 

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Dodge dealer or gm dealer less then $20 a quart on amazon it takes 4 and isn't exactly a replace it every 3 month or 30 k miles, why not just go for the piece of mind put the right stuff in and call it a day.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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i useed RedLine MT85 what came with it when i bought it from advanace adapters. But it is due for a change now that you brought up the subject.
That was in 2001, about 50,000 miles ago. No problems.
 
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