ron : NP{200 Transfer Case

NP{200 Transfer Case
Post by ron on Aug 8, 2006, 7:22am

Transfer case assembled, quick question: What type of oil do you guys use??

Re: NP{200 Transfer Case
Post by barrman on Aug 8, 2006, 7:45am

90W is what is called for.

I ran 80W-130 mineral and then switched to Mobile 1 synthetic of about the same weight.

Re: NP{200 Transfer Case
Post by ron on Aug 8, 2006, 9:17am

why did u switch to synthetic?

Re: NP{200 Transfer Case
Post by barrman on Aug 8, 2006, 11:13am

I was foolishly thinking that synthetic would run cooler and not allow the t-case to heat up. I can almost set my watch by the t-case heat. 45-50+ mph for 45 minutes="what is that smell?" followed by "have I really been driving for 45 minutes and only gone this far?" That is with no top on the truck. With the top on, my eyes start to water too. I used to stop and check the case temp with my infrared thermometer. Readings of 240-278 degrees were what I always got. Slowing to 45 mph would keep it between 240-245 degrees. That is why I am switching to a NP205. Of course, by the time I get that done, I won't be able to afford the fuel to drive faster than 45 mph even if I can.

Re: NP{200 Transfer Case
Post by robertcowan on Aug 8, 2006, 11:24am

I USE 85W140 AMSOIL. DEFINATLY DROPS TEMPS.

Re: NP{200 Transfer Case
Post by brute4c on Aug 8, 2006, 2:55pm

Doesnt help my temps Bob...some tcases just dont respond that way...

Re: NP{200 Transfer Case
Post by barrman on Aug 8, 2006, 3:10pm

Jon,
To be fair to Bob. The highest I ever got with mineral oil was 278 degrees. The highest I have ever had with synthetic is 264. I just run at 50 and don't worry about it anymore.

Re: NP{200 Transfer Case
Post by brute4c on Aug 8, 2006, 3:17pm

I have exceeded the gauges limit of 320 degrees with both....with the synthetic, I ran for bout an hour at 60 and also at 55 and reached about 240 degrees....then within 1/4 mile the temp rose dramatically to 280 and I managed to get off the road and stop....it pegged past the 320 line and I had to wait an hour or more for it to come down to the point where I could drive again...

I do 50 on the flats and downhills....I let the truck slow down on uphills by not steping into it more than I was on flat ground at 50....that worked from LBL in Kentucky to northern Wisconsin without overheating in the heat of summer.