Spring Perch Wedges

[Spacecrab]

Hi guys,

I need your advice: I ran out of gas and while feathering the '3b downhill in neutral I noticed it didn't run so smoothly and there's a mild thud which I honestly didn't notice under power

So I had a look and it seems there's two blocks between the transmission crossmember and the frame,.......... sooo It looks like without them the gearbox will whack the body or the engine and gearbox won't align

I was thinking to wedge the Dana 44  spring perches in the back so the driveline angle isn't so harsh: seems to be putting a lot of angle on the rear diff

Any advice, has anyone had this issue? Anything extra I need to think about there?

[oldtime]

Something seems hokey pokey.
We likely will need to see pics.
We really don’t know what you’ve got but crossmember drop spacers certainly are not normal.

Why so much angle at the rear propeller shaft ?
Was this Jeep lifted at the shackles ?

[Rus Curtis]

Something seems hokey pokey.
We likely will need to see pics.
We really don’t know what you’ve got but crossmember drop spacers certainly are not normal.

Why so much angle at the rear propeller shaft ?
Was this Jeep lifted at the shackles ?

Perfect technical description!

Spacecrab,
Pictures would help.  The coasting downhill is what allowed you to hear the thumping (once, occasional or continuous at the same rate as your speed)?  IF your drivetrain is stock, it won't hit the tub from underneath.  The alignment should be set with the bolts holding the components together (engine, bell housing, transmission and transfer case).  I suppose if the tub is aftermarket there "may" be a chance for contact but thicker Sill Liner's (rubber pads) between the tub and frame may be a better route than multiple changes to your drivetrain.

It is short from the transfercase Companion Flange (output) to the End Yoke (input) on the pinion.  It may also help to list what you have - in case something is being used that's non-stock.

My first guess would have been the u-joints but it may be better to approach this methodically.

[Mark W.]

What your looking for are called pinion wedges. Summit racing has dozens of different ones. I used their house brand 2° version to add a little Caster to my front axle after going to 1" longer Shackles.

[duffer]

"What your looking for are called pinion wedges. Summit racing has dozens of different ones. I used their house brand 2° version to add a little Caster to my front axle after going to 1" longer Shackles."

I didn't have much luck with the off-the-shelf aluminum wedges.  They are just too soft for any reasonably intense trail use.  McRuff (Mike) on ECJ5 will machine you what ever angle you need for those out of steel.  Or you can just make your own if you have access to a mill.  My last set for the front of the 3B I made by using a piece of 1/2" plate for a base and set the angle on the 3/4" thick x 1 3/4" wide stock with a piece of 1/4" bar stock and just tack welded together and then milled it flat (a poor man's sine plate).  I pre drilled the spring bolt hole before tack welding so they are perpendicular to the base.  I even had enough room to add a second set of spring bolt holes to move the axle 3/4" forward with those.

[Spacecrab]

Hi guys, sorry for the late reply

Had a bunch of other issues to sort out

Here's what I seem to have:

1 blocks of wood between the crossmember and chassis

2 Dana 44 pointing to the sky while prop shaft comes out straight from the transmission

I've tried to keep everything stock but seems without the blocks the top of the transfer case hits the body... but there is room to reduce them 50%

What if I use the pinion wedges to normalise the dana 44 angle?

I could get those blocks made in hard rubber, half as thick

Any thoughts are welcome...

[Spacecrab]

1.

[Spacecrab]

2.

[oldtime]

What engine and transmission is it ?

[Rus Curtis]

Don't think I've seen wooden blocks there on the cross member before.  I can definitely understand your concern for wanting the rear axle wedges.  Initially, I don't know why your axle is angled up so high - I'd wonder if it were the original axle or if the saddle is in the correct position.

You state that you're trying to stay stock, so maybe all parts came with your jeep.  I see an angle from the transfer case to the yoke but no like you describe.  For illustration, from the SM, SM-1002-R6, look at fig 15 (lubrication), showing from above and fig. 277 (hydraulic brake system), showing a side view perspective.  Neither show extreme angles at the yoke on the rear axle.

Something is odd.  More details will help to figure this out. 

[Spacecrab]

Hi all,

I have an F Head 134 and normal T90a

No lift kit although it does have the heavier amount of springs, 9 and 10

I'll measure the clearance between transmission and body tomorrow and post it up

[duffer]

I think I would just remove those wood spacer blocks and see what it looks like.  If the transmission/transfer case still clears the sheet metal like it should, there would appear to be little reason for them.  Your driveshaft angles should be much closer without them.  Ideally, the angle at the pinion and at the companion flange should be equal.  You may still need the spring perch shims but they are going to be in the opposite orientation from what is normally the case.  You can get shims made to whatever angle you want or, if you have access to a milling machine, just make your own.