transfer case I.D. ?


Junior Member
203 transfer case?
i was checking the page for transfer cases and to my limited knowledge i have a 203 in a 77 GMC 350 with TH350 full time front end.the page states that the 203 has no drain plug and the speedo cable on the drivers side.
mine has no drain plug,the fill is in the right place for a 203 but the speedo comes in on the passenger side top right looking forward at the tranny.
the 205 speedo is supposed to come in on the passenger side.
where does the 208 speedo come in?
most full time TH350's auto's have 203's,as far as i know.
any ideas on this?

Chuck Smith

2000 Club Member
Don't sweat the location of the speedo cable. At the time, I had no other to compare my 203 to. I have also talked to folks with the 205, that have the speedo on the opposite side as well.

Also, look at your shifter. If the knob looks like the 203 one on my website, and the shift pattern is the same, then you have the 203 for sure. You are correct, in 77 all auto trans equipped trucks came with the NP 203 fulltime case.

Also, if the options decal is still in your glove box, look for RPO code "1 N41" "Variable Ratio Power". That's the NP 203 t case.



Junior Member
203 transfer I.D.

thanks for the reply and info. as i said before i was almost sure i had a 203 but the position of the speedo cable was different.with two locations for the speedo it will make it harder to I.D. 203's for replacement used parts in the future.
this old girl has had so many parts replaced over it's life that i have no way of telling what is stock and what is not. thanks TUX.


Junior Member
tux, I changed my 203 out for a 205 400 automatic though so i know a little.Alot of work changed output on tranny changed crossmember made two new drive shafts theres two inches difference between the shafts on the 203 and 205. Anyhow sit in your truck and look at the shifter if its flat where it comes out of the floor then gets round at the knob its a 203.If its round from the floor to the knob its a 205 the 205 shifter is not flat coming out of the floor.Presently running two 203's and two 205's wouldnt hesitate to invest 7-800 on switching over the 205 is a monster of a case.Good luck finding one alot of been bought up by the truck pullers/competition weight pullers.Hope this helps.You can find the 205s in alot of 80 & 81 full size four wheel drive suburbans,If you do buy well spent.I recently bought one for $400 just in case I need it.

mike reeh

Senior Member
a 203 in good condition is just as strong as a 205, the weak link is the chain drive, keep it in good working condition (read: preventive maintenance) and you will not have a problem. If you arent into the full time 4x4 thing, install a part time kit (i did) and you'll have the strongest, nicest shifting, most reliable 'case on the block.


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