Thread: Transfer case lube?

What type of lube goes in the transfer case of my 83 K10 diesel?

since you have the 700r4 tranny i assume you have a np208 transfer case. it takes dextron 3 transmission fluid only!!!! if someone swapped in a np205 it takes gl5 80w-90 gear oil. or if you have a np203 fulltime case it takes 10w-30 motoroil only!!! the 208 is original equipment and is all alumium. the 205 is all castiron, and the 203 is castiron with a alumium tail shaft. my manual reccomends you change the t-case oil once a year reguardless of milage. hope this helps

Thanks Ken. I must have the 205 as the portions of it I can see thru the grime look to be alum.

I meant the np208 in the above post. Thanks again.

Any idea as to how much atf the NP208 transfer case will hold?

Brett

On my truck,the other day I drained the transfer case.It has a 208.It took 3 litres to fill.Well, close to three is more like it.

Thanks!

Personally I have always drained out the ATF and used 0w-30 synthetic engine oil. The big reason for ATF is easier shifting in cold conditions Big deal I would rather have something in there that is a good lubricant....ATF is not. My .02

The use of ATF is very common in both manual trans and transfer case applications. The criteria for these applications is to have a lubricant with good anti-wear additives and also provide excellent flow to the bearings in the unit. Many people make a mistake by putting thicker gear lubes in these units. Gear lubes are made to handle the heavy loads and the contact and slide operation of the ring and pinion gears in a differential. The Extreme Pressure (EP) additives in GL's are sulphur based and will chemically attach to the surface of the metal under load. When the oil film gets blown away the EP will prevent steel to steel contact and that is where the wear would occur. Since there is no contact slide in the transfer case or the transmission (simple bevel gear sets)then only anti-wear lubes are required. Anti-wear additives such as zinc are only loosely attached to the surface and can be easily scraped off in contact and slide appliations.

So the use of ATF is correct for the transfer case and the use of motor oil would be a qualified second choice. Don't forget the use of automatic transmissions is prevalent in heavy duty applications and the ATF has to lube all the gears and bearings in those HD auto trans. Synthetic ATF is superior to petroleum because of the synthetic basestock not the anti-wear additives. The temperature range of synthetic is more than twice the petroleum and the natural film strength is more than twice the petroleum.

One last thing to note: most gear sets (transmissions, transfer cases etc) have bearing failure much more than gear failure. Why is this? Because people use a thick gear lube where they should have use a light weight oil such as ATF and the bearings get starved for oil. The thick stuff can't get into the bearings tight clearances.

In any cas stick with the manufacturers recommendation in the owners manual. They know what it is designed to take and that is the best bet.

ALT Dan Watson
www.AdvancedLubeTech.com
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Originally posted by ken
since you have the 700r4 tranny i assume you have a np208 transfer case. it takes dextron 3 transmission fluid only!!!! if someone swapped in a np205 it takes gl5 80w-90 gear oil. or if you have a np203 fulltime case it takes 10w-30 motoroil only!!! the 208 is original equipment and is all alumium. the 205 is all castiron, and the 203 is castiron with a alumium tail shaft.

The transfer case is next on my list to change the fluid. How can I tell what transfer case I have... just look at it based on the above descriptions?? The previous owner changed a lot of things on this truck, so I can't really go off what it came with. It has the 700R4 though... '82 1/2T 4x4 suburban. 6.5L banks turbo...

Thanks!

My transfer case has a tag screwed onto the back side of it.

Brett