1978 GMC K25 C4 Transmission Parts

The 700R4 is a great choice when it's time to upgrade your classic car or truck with an overdrive transmission. Here's what you need to know about GM's famous 4-speed automatic.

Follow along as Jeff installs an early 700R4 transmission for the big block in his 1967 Chevelle. See how this unit is upgraded and converted to a later 30 spline style.

In this episode of our C10 build series, we swap cams in a junkyard 5.3 and make surprisingly big power.