K10 4-speed

My buddy has an '85 K10 with a 4-speed manual transmission. The fourth gear is overdrive. I am buying the transmission from him to put in my Malibu and I was wondering if anyone could tell me what transmission that would be. I know how to identify them by looking at them but the problem is that I am not going to be able to look at it for a while and I would kind of like to know.

The only 4 speed overdrive in these years is the 700R4...a very dependable transmission that can be built to be even stronger. Some people may tell you these transmissions have problems but we have had nothing but good luck with them, ask a trans specialist and they will most likely tell you how good they are.

Ok, so my buddy might be wrong about the overdrive but It is a manual transmission, not the automatic. And you are right about the 700-R4 tranny, it is a very reliable transmission although some of the first 700's had some problems but the later ones are solid. If you put the right components into a 700-R4 and do some other mods, it is not unheard of for them to handle 700 hp without problem. Anyways, if the transmission is a normal 4-speed, without overdrive, what kind would it most likely be?

That 4 speed manual you spead of would be a SM465. It has lots of other "nick names" like bull dog 4, granny 4, all meaning that first gear is non syncronized, but ultra low, about 4:1 ratio. This is not something you would want in a car. It is made for trucks, being very large and strong. It does not have overdrive but is considered the tuffest manual made for the chevy truck till it was outdated. It was used up to about 1992 where it was finally replace with the NV4500. The NV4500 has overdrive but is still a large manual, not suited for a car.

Hope this helps.

i have the SM465 in my K10 w/ 305, NP205, GM 10 bolts w/ 3.08's, and 33" Buckshot Mudders. It is a huge, heavy cast iron trans. Ratios are:
6.58, 3.27, 1.57, 1.00. 1st is not syncronized, and third is too far from second. trust me, you dont want this in a car!