I have a 400 sbc mated to a 400 turbo trans with a np203 t-case. with the engine off and the trans in park and the t-case in 4 low should the driveshafts still turn??? I wouldn't think so, but they do. I just pulled them out of a 79 3/4 ton chevy today I had to use a pry bar to get the drive shafts off. would this be because it may have open axles??? I would still think that the trans would still lock the driveshafts from turning when it was in park.
Any comments or help would be greatly appreciated. Thanx Gary
how much can you turn them? like a few degrees or the truck rolls around freely? just a few degrees is nothing to worry about. if you can roll the truck around then either the t-case doesn't lock in to gear fully, or the parking pawl inside the trans is broken.
You can turn the drive shafts all day and the axles don't move. but the trans or t-case don't stop them from moving either.
Here's the poop on an NP203. This is a full time transfer case with a "loc" position for slippery conditions. When you are in Hi or Lo but not in Loc the transfer case will act like a differential when both axles are off the ground. If the t-case is put in the Loc position then you should not be able to turn the driveshafts.
lock your hubs but shaft shoudn't free spin
no lockouts they are automatic (have caps over the end of the axles) you free spin the drive shafts with the tires on the ground.
there not auto hubs there full time locked just with slugs in them but...were missin part of the story here cuz if you can turn both shafts "all day long" and the axles dont turn you got problems front, rear and center
with a 203 you don't want auto hubs they need to be fulltime hubs (AKA buiskets) or manuals left locked. have you pulled the cover off the front diff and checked the spiders ??? if you put it in the lock position can you still spin the front shaft ??? if so the chain is broke (this is fairly common)
Call me tomorrow. Around 2. I'll fill ya in.
now I'm even puzzled.........
Are you sure the tranny is good?
2nd.........if you can turn either driveshaft and the opposite one spins at the same time ( in HI LOC or LOW LOC )............then its not your T-case chain. I can't see your chain being broken.......because Np203's use a hell of a heavy duty steel chain..........I've never seen or known anybody who's broke or snapped one before. They can stretch over time..........and thats mostly due to it being a full time T-case and chain is always spinning inside.
3rd.............it might be possible that T-case is worn out, since its full time there are parts inside it for the ALL Wheel Drive settings that can wear out and since its at least 29 years old.......it may be time to rebuild it or replace it...........just a thought anyway.
Keep us posted...........cause I'd like to know what you find out with it. I got 2 trucks myself with 203's...........both full time..........and never had problems with them yet.
Both driveshafts spin while vehicle in on the ground? Does not compute!
sounds like either you have no teeth on the ring gears left, or pinion. open axles with broken axle shafts.. or no spider gears...
Ok after further investigation I beleave the axles in the truck are junk. I pulled the engine, trans, and t-case. But I am still puzzled because I pulled everything as one so it is still all hooked together and can still move the yokes on the t-case with the trans in park and the t-case in lo-loc.
The t-case is good because when I turn it both yokes move together with no slip or play between them. So I'm thinking trans ( shifting fork or torqe converter. or even gears them selves ) I don't know. Theoreticly I should not be able to move anything with the trans in park unless I have a t-case stuck in nuteral. I guess I will have to tear them apart and find out what is going on with it/them.
P.S. When I turn the yokes on the t-case I hear the gears or chain or all moving inside but not the trans so hopfully my trans is still good and worst case I'll need another t-case.
What are you guys thinking?
parking paw... or the actual gear the paw locks into must be blown apart then...
it was probably put into park while moving
Ok after looking at the transfercase really close this evening I was able to see that the bottom linkage rod going from the shifter to the t-case was bent just enough to not let it go into the "loc" position. I was able to heat and bent it back to it's original position and it worked I finally got it to lock in. applaudd applaudd
Thanx for all the help guys. GotMud? members are ==awesome applaudd applaudd applaudd