Moving the Rear Leaf Springs For Pro-Street On 1960s and 1970s Ford Trucks, A Basic Overview
By Wally Womack
Locate a donor truck of the approximate year. If you can get it to your shop/house life will be easier. You can cut it up a little at a time and you can use the scrap. Although to be able to cut the parts you need and leave the mess at the other location is very nice. Cut the Frame 5 to 6 inches each side of the leaf hangers on donor truck. I had a 1964 frame given to me and I didn’t notice until I had my frame parts cut and fitted that the front leaf spring hangers (from the 64 frame) sit about 3 inches higher than the original 65 truck which in turn should lower the truck.
The way I fit and bolt these frame parts up with the old mounts still in place:
Take leaf pad/perch and sit them in place. Bolt the extra leafs that you get (from Donor truck) up to frame parts. Measure off the 65 leafs in about 6 places to make sure they stay parallel to each other. At the front hangers there are two (2) chassis gussets one each side (they look like braces) under the cross member that appear to be in the way. Take a side grinder and grind the rivets to the gussets ONLY not the cross member.
If you’re thinking the removal of the gussets may weaken the frame well you can add braces at the front edge of the frame parts that you are adding. On my 65 I took and added a rear cross member from a 76 frame. It is bolted to the front edge of the frame parts and welded. The corner bracket that bolts it in is cut from scrape frame. I used grade 8 bolts. The more I sat there looking at the 65 frame the more ideas I came up with. I pulled the emergency-brake cables out of the cross member and inserted a small 1/2 inch tubing and turn it around and around to mark the holes in the 76 frame cross member that I added. Drill the holes in the 76 cross member so your emergency-brake cables can pass through it. Use a big Unibit and you can add grommets to the holes.
Your frame parts will require the top of it to be notched for the cross member. You can mark the width you need to cut when you cut your frame parts. You will have to cut across the cross member of the donor truck. You will have to grind the rivets out of the cross member of donor truck. I notched it deep enough for the frame parts to sit on top of frame and the bottom of frame parts sit inside on bottom of 65 frame. At this point you should have the hangers where they are under the cross member. You can make and fit your own gussets.
Ok moving to the rear of the truck frame, The rear cross member will have to move forward to the edge of your rear frame parts. You will have to grind out the rivets (4 each side). I took mine and cleaned it before putting it back in. Flip it backwards (the back edge will but up to the front of the frame parts). You can drill holes to mount the cross member back in frame. When you have everything bolted up and fitted right you will see that you will have to cut a notch in the rear cross member for each leaf spring to clear or the spring will hit the cross member.
They can travel up and down if it would make you feel safer where you notch for them you can box them. Be sure you don’t mix up the rear cross member. The 65 had a C5TE and the 64 C4TE. If your leaf spring bolts are in bad shape you can buy grade 8 at a hardware store. I have noticed the stock ones are grade 5. The vent tube for the rear end will work out under the leaf pad/perch and you have to grind a small amount on the leaf pad. It will work right where it is or you can drill and tap a new one.
When you get everything fitted and you have your extra set of leafs from your donor truck bolted up after grinding and fitting don’t take your old ones off until you welded your perch/pads in place and then you won’t have to set your pinion angle (because it will stay the same). On the shock mounts I used ones that you buy that use coil covers on the nine inch and at the top I made my own that go on the cross member that crosses right behind the rear end. They are in my gallery they are the blue ones and they are made out of one rear end u-bolt plate both ends cut off. I welded a piece of square tube to that in the center and drilled 2 round holes to make them adjustable at the top. I am sure you can come up with what ever you want.
NOTE: Anytime dealing with suspension there is always a risk of not getting something right and creating a danger to yourself and others. Make sure all your welds are strong and good and that you use at least grade 8 bolts. Proceed at your own risk.