ok im at a loss, i need to replenish my transfer case fluid but i dont know how to tell what it takes its a 205 and its in A 79 F150 W/351m(if it matters) i did a search but i came up empty, am i just searching for the wrong thing?

 

So i looked on my transer case and it says ch415? whats that mean?? i was told it had a np205

 

I use royal purple 75w 90 synthetic in my np205

 

i was gonna get some 80/90 and the guy said mine could take engine oil or atf also......and im not to clear on what ch415 means, do i still have an 205?

 

That sounds like a casting number-
There should be a round red and silver tag attached with one rivet in it's center that will be stamped with what the case is.
Otherwise, if it's a cast iron case with a kinda angular kidney shape, and has a round plate bolted on in the middle of the rear, it's an NP205, which is what your truck should have come with from the factory.
If you have full-time 4x4 (not very likely), then it would be an NP203 case, a chain driven iron case.

 

oh ok, ill look tomorrow but its also NOT full time thanks for the help, so do i use atf or does it really matter?

 

use 80-90w gear oil.. its a GEAR DRIVE CASE.. thats what you wanna use.. you could use other viscosities but make sure its GREAR OIL.. NP205 is GREAR drive.. and i own about 10 of them so i know..

Ray

 

Ray i am going to take your word because i have no clue so i will go to gi joes and pick up some royal purple gear oil, thanks guys for all the help in this issue

 

definetly use ONLY gear oil

 

And my GEAR DRIVE transmission uses 50w motor oil-
I do believe gear oil will work, but many cases call for ATF.
The only place I found online that says what to use is autozone.com, under repair info, and they say to use EP lube. There should be lube info on the info tag on the case.

 

chain drive cases most the time use ATF

Ray

 

I have 80/90 wieght in my np435 altho I have a np208, I still know the difference... regular atf is for the np208, the np205 uses 80/90. Regular atf is meant for quicker shifting, with shorter range between gears.

 

so say that i was supposed to use atf what would happen if i used 80/90 gear oil? slower shifts?

 

chain drive transfer case.. only use ATF in them,, they have an actual ATF PUMP in them that moves that ATF around, the great oil would be to thick and ruin them i bet.

Ray

 

um whats EP thats all the autozone thing said, but heres what my under standing is,NP208 is gear driven and an np205 is gear, now np205 is when u manually shift into 4 wheel drive and np208 is all time 4 wheel drive....205 takes GEAR oil since in its gear driven. and the 208 takes atf because its chain driven? so i need gear oil