What 4 speed do I have? 1969 c20
 

I am doing a ls swap and thinking about using this transmission. Which tranny do I have? Any input would help. My engine is all stock. And looking to get it on the road. I have this c20 4 speed that I belive to be good.
Thanks.

Re: What 4 speed do I have? 1969 c20
 

Looks like an sm465 to me.

Re: What 4 speed do I have? 1969 c20
 

Ditto, 465

Re: What 4 speed do I have? 1969 c20
 

Thanks folks

Re: What 4 speed do I have? 1969 c20
 

How long has it been sitting like that? The shift tower is open to any rain and snow that chooses to fall on it. Even odds are it will be full of water.

Re: What 4 speed do I have? 1969 c20
 

It’s all good. No moisture. From what I have gathered this transmission has a extremely low first gear. Does this sound correct?

Re: What 4 speed do I have? 1969 c20
 

YUP! AKA Granny gear.

Re: What 4 speed do I have? 1969 c20
 

What are your goals for the truck? How are you configuring your swap motor? The SM465 is an awesome trans for a working truck. The deep first gear makes offroading and towing possible with moderate gear ratios.

But if you are looking to build a hotrod type street machine, the SM465 is the wrong transmission.

I ran a big cammed 327 in my Jimmy and the torque characteristics were completely wrong for the gear split on the 465. With the 210@.050 cam that is in it now, it works great.

Re: What 4 speed do I have? 1969 c20
 

Granny is 6.55:1. You won't use it unless farming or rock crawling. And that's ok, just something to be aware of.

Re: What 4 speed do I have? 1969 c20
 

My 4x4 has 3.07 differential gears and 33 inch tires and 1st gear even with that set up is pretty much un-needed on the street. You'll be left with essentially a three-speed. As somebody else mentioned it is a fine transmission for a working truck, I tow a 4,500 pound travel trailer and will use 1st to get things moving.