transmission id

[drivethechevy]

my 68 k10 came with 2 granny gear 4 speed trannys, one is instaled in the truck and matted to my rockwell 221 where it will stay so i wanna know what my tranny is, the installed tranny has the standard shift patern 1234r, here are a couple pics of it



im thinking the second tranny that was in the bed of the truck is an older gm tranny but i may be wrong, the patern is r1234 which is different then the ones im used to and it doesnt look like it can be mated to a t-case
so im guessing a 2 wheel drive, here are a couple pics of its casting numbers



thanks alot guys
nate

[BobS]

Nate,

The one in your truck is a SM-465, the other one is a SM-420, it was used in GM trucks through 67.

Bob

[justcuz]

Not sure but I think the 420 has a lower granny. Reverse is were on each trans? I thought the 420 was left and back, I have one in the garage, just too lazy to go look! Does the 465 have an aluminum top cover? when did they stop using that transmission?

[drivethechevy]

thanks bob
what are the ups and downs of both trannys?
was the sm-465 used in 2wheel drives?
what trannys might have been used in a 70 gmc 2 wheel, sry no pictures of this one

[drivethechevy]

Originally Posted by justcuz

Not sure but I think the 420 has a lower granny. Reverse is were on each trans? I thought the 420 was left and back, I have one in the garage, just too lazy to go look! Does the 465 have an aluminum top cover? when did they stop using that transmission?

reverse on the 420 is left and down, on the 465 it is right and down, it looked cast when i was out messing with my truck earlier, but its caked in grease and paint, its possible that its aluminum though

[BobS]

The SM-420 does have a lower first gear and it's shorter, not really advantages in our trucks but it makes a big difference to the rock crawling crowd. The 465 is a lot easier to find parts for, they were used up into the late 80s or early 90s, not sure exactly when they went away. They were used in both 2WD and 4X4s. The transmission with the aluminum cover is the NP (New Process) -435, they were only used in 2WDs, mostly camper specials and the like.

Bob

[justcuz]

Thats what I remembered on the 420. Both are great transmissions with the 420 being a little noisier (older style transmission).

[drivethechevy]

thanks alot for the info
nate

[justcuz]

Originally Posted by BobS

The SM-420 does have a lower first gear and it's shorter, not really advantages in our trucks but it makes a big difference to the rock crawling crowd. The 465 is a lot easier to find parts for, they were used up into the late 80s or early 90s, not sure exactly when they went away. They were used in both 2WD and 4X4s. The transmission with the aluminum cover is the NP (New Process) -435, they were only used in 2WDs, mostly camper specials and the like.

Bob

And the NP 435 were used in Fords and Dodges too. The 420 is popular with the Jeep guys, you can run the 420 with Dana 18 gears in a Dana 20 t-case and make a real crawler out of a Jeep. Popular in the late 60's early 70's behind the little Buick V6.

[chevy29267truck]

nice transmission nate i have a four speed in 67 chevy 3/4 ton long wheel base truck how many diffent four speed trannys where put in the 1967-1972 chevy trucks one other thing dont lose or let any one take your four speed shifer,rod if it happent north west transmission from OH has them for $100 with the parts that go on the end of the shifter,rod

[chevy29267truck]

what four speed transmission is this

1 3
n
2 r

[chevy29267truck]

i mean the one 1 than2 3 n 4 r

[drivethechevy]

Originally Posted by chevy29267truck

nice transmission nate i have a four speed in 67 chevy 3/4 ton long wheel base truck how many diffent four speed trannys where put in the 1967-1972 chevy trucks one other thing dont lose or let any one take your four speed shifer,rod if it happent north west transmission from OH has them for $100 with the parts that go on the end of the shifter,rod

thanks for that info, ive got a spare 465 so i should be fine, and the 420 probly wont be around to much longer

Originally Posted by chevy29267truck

i mean the one 1 than2 3 n 4 r

all i know about trannys that came in these trucks is from this thread, but that sounds like a standard manual shift patern