NV-231 Transfer Case Fluid Issue

[Jim Cissell]

Greetings. As a new member of this most excellent site, I have an important question to consider. I have a 'New Process Gear' NV-231 transfer case in my 2000 Jeep Wrangler. I have neglected the fluid check on this particular component and recently discovered that I was 22 oz. low! What upsets me is I'm very retentive about the other fluids - especially the oil and transmission - but I simply overlooked this one over the years!

When I initially checked the fluid, I put my index finger in and saw some fluid on it, so initially I wasn't alarmed. But once I started adding, I was shocked it required 22 oz of (measured) fluid to bring it to the fill-hole. According to the field service manual, the transfer case holds 40 oz. (total) of ATF+3 fluid. The fluid looked normal - not perfectly clear, but not dark by any measure, and it didn't smell burned or anything like that.

The manual shows the transfer case has an 'oil pump' and a pick-up tube as part of it's design, so I was hoping that even with a half-filled case, the component was getting adequate lubrication because of this set-up.

The vehicle has never been in the 4-wheel drive mode (sorry!) but it is indeed a daily-driver. Do you folks think I have caused some potential long-term damage, or are these transfer cases more forgiving than I may think?

Thanks for your insight and advice,
Jim

 

[wrangler]

OUCH, that more than a quart. What's the total capacity? The owners manual says 1.5 quarts, the FSM says 1 Liter, I think when changed out my fluid it was about 1.5 to 2 quarts to the fill hole...

I'm assuming if it's still running you're OK...

 

[Grossomotto]

Half full? It's fine. Just think of all the people that run their ENGINES half full with oil!

I'm low on transmission fluid and just too lazy to get another QT to reach the "full" mark.

 

[Greaser]

The NV231 T case on the "Command Trac" epuipped Jeep vehicles is a tough,simple design that can take alot of neglect.You will not have a problem with the thing with just a low fluid check (a drain &fill would have been more appropriate though).I change my T case fluids once a year on my 231 and my 242 epuipped Jeep vehicles,thats overdoing it a tad I guess,but it's part and parcel of my maintenance schedule.Don't forget your axles!

 

[Sparkman]

The 231 doesn't hold much fluid, and running it low is going to stress the fluid that does remain. I recommend changing it with a fully synthetic ATF and keeping an eye on the level.