What are yall runnin in your 205s, specifically an 86 cucv.

I know a lot of newer trucks are runnin ATF but didnt know if the 205 was still gear oil or ATF.

TIA

1st, are you sure it's a 205? There were only a couple CUCV's that came with a 205. The vast majority have a 208.

203 takes 30W motor oil
205 takes 75/90 (30w if under 10 deg F)
208 takes ATF

NP205 takes 90 weight.

if its aluminum, it aint a 205.

Royal Purple Synthetic Max-Gear Oil :flipoff2:

ok, listen closely.... wait.. youre reading, sorry.

let me say this again, one more time, in english.

A New Process model 205 Transfer case (which is a part time, gear driven, non-chained, direct powerflow design transfer case that is housed in a cast iron body) requires the use of either 80-90 weight gear oil, or 85-140 gear oil.


If I have to explain this any further, you will get a fawkin picture.

as I stated before, if its aluminum, its NOT an NP205. if you cant tell the difference between cast iron and aluminum, you might want to go back to high school physics class and ask the teacher to throw some of each at you.

ha ha, just like the 203 and some other cases they are spec'd differently by veh, mfg. dodge says atf.

in the end it doesnt matter, as long as its not water it will be fine. i run 80-90, but i got a 5g bucket of the stuff so i use it as much as possible.

ha ha, just like the 203 and some other cases they are spec'd differently by veh, mfg. dodge says atf.

in the end it doesnt matter, as long as its not water it will be fine. i run 80-90, but i got a 5g bucket of the stuff so i use it as much as possible.

In the end, it does matter. 90 weight provides more of a cushion than 30 weight, or ATF. It is used where direct contact of two gear surfaces happen under great stress.

If you have an Np203, you use 30 weight. why? because it has both gear reduction and a chain drive. the low range reduction is gear to gear. it is not planetary gearing. it is cast iron, but is not gear driven to the front axle. thats why it needs 30 weight

the NP208 is an ALUMINUM transfer case. it takes ATF, just like most of the rest of the ALUMINUM transfer cases that have planetary gearing and that dont have a viscous coupler inside.

I use ATF because it leakes from the th350 into the t-case. I pull the fill plug and drain some out every so often.

So what If I have an NP205 behind a sm465? can I use ATF then:flipoff2:




:stirthepot:

So what If I have an NP205 behind a sm465? can I use ATF then:flipoff2:




:stirthepot:

Sure, if you want to it will work fine. :flipoff2: Either will work fine in a 205. I would guess that GM/US military spec'd ATF for the CUCVs.

some old gm tech bullitens i have somewhere, say to use 10w30 motor oil in certain year 205 and 203 t cases. I use mobil 1 because i have like 20 cases of it.

Sure, if you want to it will work fine. :flipoff2: Either will work fine in a 205. I would guess that GM/US military spec'd ATF for the CUCVs.

I would guess that the US military used the NP208 transfer case in most cucv pickups. the np205 was available in the ambulance and tool trucks, not in the generic run of the mill cargo truck.

How do I know? Lets just dont ask me how I know.

as for using ATF in an np205, sure itll work. for a while. as long as you dont put it under a HUGE load for extended periods. So would water, for that matter. the transfer case is robust enough that it will take some maltreatment by the user and still operate.

Please dont spread misinformation that all CUCV pickups were equipped with the np205 when very few really were. You make the chevy guys look like the ford and dodge forum.

a rule of thumb is that if the case is cast iron, use a gear oil, or in the case of the np203, you need to use 30wt motor oil.

can you get away with using something else? sure. for a while.

You make the chevy guys look like the ford and dodge forum.

:lmao:


Why would you want to run anything else but gear oil in a 205? Heavier oil offers much greater protection under severe pressure gear loads. I don't doubt that 30w would probably be fine in a 205 under very light use, but 80w90 would protect much better under hard use, so why not use the best stuff for the job? If you're working in Antarctica, sure, a lighter oil might be called for, but if you're just looking to save .0000000003 MPG while on the trail by running a lighter oil, you've got a screw loose.

As to the 203, the only reason for the 30w is the big, wide chain. Otherwise, the helical gears in the reduction unit are basically just like the gears in the 205. That's why you can run gear oil in it when only the range box is used in doublers.

For sake of argument, I have HEARD that the syncro'd version of the 205 calls for 30w, but I'm not sure if this is true or not. They were made right around '86 or so, weren't they?... :evil::stirthepot:

:lmao:


Why would you want to run anything else but gear oil in a 205? Heavier oil offers much greater protection under severe pressure gear loads. I don't doubt that 30w would probably be fine in a 205 under very light use, but 80w90 would protect much better under hard use, so why not use the best stuff for the job? If you're working in Antarctica, sure, a lighter oil might be called for, but if you're just looking to save .0000000003 MPG while on the trail by running a lighter oil, you've got a screw loose.

As to the 203, the only reason for the 30w is the big, wide chain. Otherwise, the helical gears in the reduction unit are basically just like the gears in the 205. That's why you can run gear oil in it when only the range box is used in doublers.

For sake of argument, I have HEARD that the syncro'd version of the 205 calls for 30w, but I'm not sure if this is true or not. They were made right around '86 or so, weren't they?... :evil::stirthepot:

82-86.

but they still required 90wt.

if you ever look at an sm465, you will notice that the synchro assy looks surprisingly familiar to the one inside that NP205. funny that.