GMC K25 700R4 Driveline and Axles

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.

This resource contains a transmission pan shape ID chart and other tips to help with identifying GM transmissions.

We show you how to keep that old GM transmission when swapping in an LS engine. Our LS swap adapter kits make it easy!

We help determine what are the best 10-spline quick change gear ratios for your street or racing needs

We will show you the differences among traditional I-beam and tube axles and suspension designs used on hot rods; the differences between cross and traditional steering, measuring for springs, what spindles to choose, and much more.

In this Tech Tip, John answers a customer question about finding the right axle length for his 1931 Model A.

The Speedway Motors Tech Team created a quick how-to on squaring the front axle of your open wheel race car.

With the coil-overs attached, it is now time to make the Chevelle rear whole again. Follow along as Jeff installs a 9" third member and spline axles with a few tips on axle lengths and bolt patterns.

Learn how to assemble the front axle of a sprint car. See what tools are needed for assembly including an angle finder gauge tool and king pin reamer.