Leaf Spring Perches
All my spring perches are $140.00 shipping included in the USA.
I do not ship internationally.
Since TT's is best known for its front FSJ Spring Over Axle Perches
we will start with those but there are others, if you don't
see what you are looking for keep scrolling down.
This TadPerch thing all started a little over 17 years ago here: Link
Since that time there have been over 1,400 sets of FSJ SOA perches
sold, a lot more if you were to count all the others perches.
So this happened...
It took a bit to get it correct but it really was not hard, I simply kept
playing with the radius until I got it right for the diff side then I
created the tube side.
Pretty simple concept, I'm sure someone thought of this before but
what most folks were doing was getting generic D44 perches and
grinding one perch to fit then figuring out how to match the height,
typically with a small block acting as a shim.
So what is the X for?
I make every perch by hand, center punching, drilling, fitup and
the welding is all manual and I could be off by 1/32", maybe
even 1/16", you would never notice this as long as they were both
off in the same direction. So just point the X marks in the same direction.
So what is this extra piece below?
Not all our differential housings are created equal.
we have the 74-79 passenger drop front differentials and the
80-91 driver drop front differentials. My experience is that the
castings get a little sloppier the further along in each of those
year spreads. This is a 1/4" thick shim, it's included just in case
you can't get the height close enough.
If you are 3/16" off from one perch top to the other weld it on the
lower side, if you are within 1/8" just recycle it.
It's all about repeatability.
I make other perches for the rear, these come in handy for
axle swaps.
There is a version that fits rear GM 12-bolt, GM 14-bolt,
Dana 60's and the Ford Sterling
There is also a rear version that fits Dana 44's, Ford 9",
GM 10-bolts and our M21 (what most folks call the AMC20).
How can they fit that many models?
They are able to do this because you are not trying to build a circle
around a circle, the radius of the perch lands only on the upper area
of the axle tube.
I have the cut file for D70's but it's not a big selling item, if you need
those or something custom don't wait until the last minute, plan ahead.
There is also this thing that happens to folks using the highly sought
after 78-79 Ford high pinion D44 and D60 front axles.
You found them, they are close and a decent price, but someone
has cut the tube side perch off because they were planning on
linking the front suspension (they will typically not mess with the
perch cast into the differential housing as it's too much work.
Those don't look like your other 7" antiwrap perches?
They are not, they need to be the same physical size as the
cast perch on the differential housing, if not you will setup a
situation where you have different spring compression rates.