(powered by Google)


  Technical Articles

  Factory Literature

  Discussion Forums

  Photo Galleries

  The BumpWiki

  Service Bulletins (TSBs)

  Decoding Your VIN

  Diagrams & Schematics

  Links & Resources

  In the Movies

  Member Meet & Greets

  In the Media

  Site Index


  My Truck Projects

  My Heinz 57 '67

  I've Been Censored!


You are here: Home Tech Articles & Tutorials Front/Rear Differentials Welding Leaf Spring Perches
Back to Technical Index

Welding Leaf Spring Perches

By Tom Zuloaga Jr.

By Tom Zuloaga Jr. for     

For those of you that have ever needed to weld a pair of leaf spring perches on a rear end housing, this tip could save you some aggravation. I use a perch jig to weld the perches on rear end housings at my shop. It probably sounds expensive or complicated, but it is not. All it is, is a piece of steel that you can bolt two pieces of 2" x 4" rectangular tubing to that will locate the perch centers. A piece of 5' long x 4" channel iron works well as it allows you to access the bolt that will hold the rectangular tubing in place. You will need to drill two holes in the channel at the exact center to center distance of your leaf spring perches. (Mustangs have a 42 3/4" center to center distance.) You will need to cut two pieces of rectangular tubing 5" long. You also need to accurately drill a two 3/8" holes right in the middle of the tubing on each side (the narrow side). A 3/8" Allen head bolt is inserted through one hole, and a nut will hold it in place. The Allen head portion will simulate the center bolt of the leaf spring. (You may need to grind the head down slightly to fit some perches). The other side will bolt to the channel iron.

Here is the rectangular tubing bolted to the channel iron. The channel has a slot as I use this jig for any kind of perch distance, so all I have to do is slide the rectangular tubing pieces to whatever center to center distance I desire, make sure they are square to the channel, and lock them down.

You place each perch on each side of the jig and level the jig each way.

You then place the housing on the jig on top of each spring perch. You measure from the edge of the housing to the edge of each perch until both measurements are exactly the same. With the jig level, rotate the housing so that if it had a center section in it, the pinion would be pointing up 5 degrees on your angle finder. I know some of you are thinking that 5 degrees up is wrong, but trust me, ALL leaf spring equipped Fords are 5 degrees up. As a matter of fact, so are almost all leaf equipped vehicles, regardless of make. Once the housing is bolted in the car, the pinion will usually point down. If you are building a race car, now is the time to adjust the pinion angle, I usually point it up to 2 degrees.

(WEBMASTER'S NOTE: Ford cars are set at 5 degrees up....I'll have to check to see what Ford trucks are set at. Please research this before welding on your truck's rearend!)

Once the angle is set, re-check the side to side measurements, and tack weld the perches on. Weld half of each side of each perch, and then go to the other perch so that you will not concentrate too much heat in one area at one time and warp the housing. This is an easy method that will really pay off especially if you are going to do more than one housing. It sure beats bolting everything in the car, tack welding the perches on, and then un-bolting it all so you can weld everything. I do dozens of housings each year, and it is foolproof.


You are here: Home Tech Articles & Tutorials Front/Rear Differentials Welding Leaf Spring Perches

Want to link to this site? Please save this banner to your hard drive to place on your webpage.
The correct link to use is

Copyright 1999-2018 unless otherwise noted. All rights reserved.
All brand names and product names used on this website are trade names, service marks or registered trademarks of their respective holders.  
No portion or content of this site may be reproduced or otherwise used without explicit permission.
To report problems or provide comments or suggestions, please click here.