Sm465

[4x4K10]

If i were to go to my local junkyard and find a truck with an sm465 what would i need along with the transmission in order to swap my auto to manual? i know hydraulic clutch is better but i would also be willing to use the mechanical setup. These transmissions arent very easy to find around here. Thanks!

[silverbear]

What year is the truck you want to put the SM465 in? Does it have the low hump or high hump floor?

The first things I want to mention are some small parts but it makes the swap go better.
1. Hydraulic clutch setup: make sure you get the reservoir and the bracket it mounts to.
2. the wiring for the backup sensor. It goes from the trans, through the fire wall and plugs in under the dash. Get all of that.

Bigger items.
3. Everything from the flex plate to the trans/transfer case mount.
4. Pedal assembly. The clutch release switch should be parts of this assembly.

There may be some other items you may need that I can't think right now. Make sure to take a buddy with you to move this trans around because it is not light.

[tucsonjwt]

I can't answer your question, but just a thought. Are you very familiar with the SM465? They don't call it a granny 4 speed for nothin.

They are a very old school manual transmission. The one in my C20 has a sloppy shifter, which is normal (so I am told), but can be irritating to the fussy driver. It is nothing like a modern 4 or 5 speed. First gear is never used, and it winds up to 4th gear very soon after takeoff (about 35 mph with my 454/ 4:10 rear axle.) So, you really have a 3 speed transmission.

You do need the big floor hump, but some have hacked a hole out and installed a patch cover.

On the plus side, rebuilt SM465s can be had for about $650 from a reputable shop. The core value is about $250.

I like my old SM465, but I don't drive it very much. If it was in a daily driver I think I would prefer a modern 5 speed. My 83 still has a mechanical clutch, and I hasn't given my any trouble, aside from just being old and worn out some.

Just sayin' - you won't win any drag races with a granny.

[tgh117]

Yea as was said above. Its not meant for a fast truck for any reason. Mine actually isn't too bad, but I am running 35's and 3.73's. It still won't win any races.

Anyway you need the flywheel, clutch setup, trans, possibly the transfercase as well depending on what is in your truck now, and you will need the crossmember, the pedal assembly from in the cab, the linkage setup that bolts to the frame to connect the pedal to the throw out bearing, and the taller hump from the cab to run something like that for sure.

You will also likely have to at least your rear drive shaft assembly redone. Front might have enough length.

My buddy went from a TH350 to SM465 and I think he only had to have the rear drive shaft redone, but I can't full recall.

Its a pretty big job, and that trans definitely has some weight to it. Good luck.

[Jeepwm69]

Very heavy duty transmission, but good points listed above.

At the risk of sounding like a wuss, our non-hydralic clutch equipped 83 will flat wear out your left leg if you drive it in traffic. It's not a problem where I live, but on one of the few trips it's made to the city, constant shifting with the 40 lb spring that apparently is on the clutch wore my leg out

[MalibuSSwagon]

In comparison, my 86 with the hydro clutch is very easy to shift, the pedal is effortless. I would certainly recommend the hydro clutch conversion.

[68Timber]

Depending on how anal you are, you might want to swap to a manual trans steering column.

[tucsonjwt]

On the other hand, my left leg is the only part of my body that gets a work out these days. At least that is some kind of workout. I guess my spring must be worn out, because it doesn't feel too stiff to me. I like simple things.

[Tucson38]

The SM 465 seems pretty indestructible but it has some drawbacks, one of them being a large gap in the gear ratios. In a perfect world this tranny would still have the super low first gear but another gear between 3rd and 4th, plus an overdrive gear but still have it's rugged quality. But I guess that's way too much to ask.

[TwoFiftyShifter]

I have had 3 of em. Half tons, clutch is bare able. I had a 3/4 ton with a hydro clutch and it was a butch in traffic.

This trans is sturdy, but old. Slow shifting with big gap between 2-3. I love it, however.

[Shyguy]

I use to have a '72 GMC 3/4 ton with a SM-465 and I used the low gear when I was launching a 26 ft cabin cruiser and pulling it out of the water. My present truck is a '67 C-10 with a 454 and a SM-465, I use the low gear working around our farm.

[cory d]

old pile of crap, useless off the trails/farm, giant gaps in the gears. whines really loud. have one in my truck. i love it!

[tucsonjwt]

I bought my 83 12 years ago and it came with a gear vendor under/overdrive from the previous owner who used the truck to haul a truck camper. Still, the GV only is used when shifting into third gear and fourth gear, so I really don't use it in the city - stop and go traffic means it would not be in GV mode very long. The cost of installing/maintaining a gear vendor overdrive makes it impractical to put behind a SM465.

[MalibuSSwagon]

Yes I almost forgot, the noise. It's loud and the tin can cab only makes that more apparent.

[68Timber]

Originally Posted by Tucson38

The SM 465 seems pretty indestructible but it has some drawbacks, one of them being a large gap in the gear ratios. In a perfect world this tranny would still have the super low first gear but another gear between 3rd and 4th, plus an overdrive gear but still have it's rugged quality. But I guess that's way too much to ask.

That would be the NV4500.

[cory d]

nv4500 would be sweet. my buddy might put a nv3500 behind a 292

[Edahall]

Originally Posted by Tucson38

The SM 465 seems pretty indestructible but it has some drawbacks, one of them being a large gap in the gear ratios. In a perfect world this tranny would still have the super low first gear but another gear between 3rd and 4th, plus an overdrive gear but still have it's rugged quality. But I guess that's way too much to ask.

Originally Posted by BRUISER

That would be the NV4500.

The NV4500 has the same large gap between each gear as the SM465 but has the addition of an overdrive. Speaking of less gap, the NV5600 6 speed transmission is the one you may be thinking. It is also a lot more robust transmission than the NV4500 and shifted better. The NV4500 had issues with the 5th gear nut backing out.