77 Axle wedge

[Greg7764]

New to me 77 bronco, was told it had a 4" lift.
There aren't any wedges on the rear axle, and it's throwing off the driveline angle. What's a good wedge to start with? tia.

 

[rocknhorse76]

The 6 degree steel shims offered by most bronco vendors are used a lot.

 

[DirtDonk]

Are you getting a vibration under deceleration? Or are you just going by the visual?

You can also confirm the amount of lift by measuring between the top of the axle tubes and the bottom of the frame rails.
The approximate measurements of a stock height bronco are 7 inches in the front and 6 inches in the rear. So if you have 3 1/2 to 4 1/2 inches above that, you are indeed working with a 4 inch suspension lift.
However, wedges/shims are not the only method of pinion angle correction.
Some people that lift broncos use re-welded spring perches, or custom made axle housings that already have the perches welded at the correct angle.

Is your bronco otherwise stockish? Has anything been done to the steering linkage to correct for the lift? Any other obvious modifications that you can tell us about?
What size tires is it running?

 

[Madgyver]

I rotated my spring perches. Before and after pics

 

[Greg7764]

Are you getting a vibration under deceleration? Or are you just going by the visual?

You can also confirm the amount of lift by measuring between the top of the axle tubes and the bottom of the frame rails.
The approximate measurements of a stock height bronco are 7 inches in the front and 6 inches in the rear. So if you have 3 1/2 to 4 1/2 inches above that, you are indeed working with a 4 inch suspension lift.
However, wedges/shims are not the only method of pinion angle correction.
Some people that lift broncos use re-welded spring perches, or custom made axle housings that already have the perches welded at the correct angle.

Is your bronco otherwise stockish? Has anything been done to the steering linkage to correct for the lift? Any other obvious modifications that you can tell us about?
What size tires is it running?

 

[Greg7764]

The spring perches are definitely at a down angle. There is a vibration on acceleration and deceleration. Running stock 15" at the moment, but have intentions of getting 30 or 33" in the near future. Will get some measurements in the near future.
Also vehicle has a noticeable low tilt to the left front and high in the right rear. 1" lower in LF, 3/4" high in the RR opposing corners are more in line... would I need a 2" coil spring spacer to correct this? TIA

 

[Speedrdr]

If you haven’t checked and/or replaced your body mounts yet, I’d check them before I went to spacers in the coil springs. I thought I had a major frame problem until I started looking closer. Two of the body bushings are absolutely smashed flat and it is giving mine that oddly cocked stance.

Randy

 

[Greg7764]

If you haven’t checked and/or replaced your body mounts yet, I’d check them before I went to spacers in the coil springs. I thought I had a major frame problem until I started looking closer. Two of the body bushings are absolutely smashed flat and it is giving mine that oddly cocked stance.

Randy

Wouldn't that tell tale sign be the body doesn't set level with the bumper? This one the body sets level with the bumpers.

 

[Greg7764]

https://www.dropbox.com/scl/fi/3lgn...2307.jpg?rlkey=59afrop3bla6zxr8ryidg737a&dl=0

https://www.dropbox.com/scl/fi/qggb...2038.jpg?rlkey=i60i3jektg1eph2opnu7a193i&dl=0

 

[Greg7764]

https://www.dropbox.com/scl/fi/990m...1948.jpg?rlkey=y229aux6fl925iaasiyxlqf7o&dl=0

 

[Greg7764]

https://www.dropbox.com/scl/fi/6cxs...1718.jpg?rlkey=bl900xf7pwlj1e9c229gy5te6&dl=0

 

[Greg7764]

https://www.dropbox.com/scl/fi/iu34...1101.jpg?rlkey=tp49n6lx3k1qy3xjeklv8eu23&dl=0
https://www.dropbox.com/scl/fi/qy42...1435.jpg?rlkey=9oofb4yyr67c8hfbl74yecg7h&dl=0https://www.dropbox.com/scl/fi/qfil...1145.jpg?rlkey=x8obb18vyqsy19hym9jn5hu4p&dl=0

 

[Greg7764]

https://www.dropbox.com/scl/fi/cbb7...1048.jpg?rlkey=3q8qnttq9ywtg1545v9co3gms&dl=0

 

[Speedrdr]

Unless I missed something in one of the pics, everything looked reasonably new; however, I didn’t see any body mounts/bushings. I would post the pic bumper showing the level REAR bumper (there wasn’t a front bumper) but I’ve torn enough parts off that it doesn’t really resemble a vehicle.
The front passenger body bushing and passenger floor are shot, giving that lovely “lean”. my springs, front and rear side to side are even measured. See pics.
Does this make sense?

Randy

 

[Greg7764]

Unless I missed something in one of the pics, everything looked reasonably new; however, I didn’t see any body mounts/bushings. I would post the pic bumper showing the level REAR bumper (there wasn’t a front bumper) but I’ve torn enough parts off that it doesn’t really resemble a vehicle.
The front passenger body bushing and passenger floor are shot, giving that lovely “lean”. my springs, front and rear side to side are even measured. See pics.
Does this make sense?

Randy

I'll give the body mounts a good look over, those areas are suspicious on this one too.
It's packed into a corner till I get the tanks both installed and fresh fuel in them.

 

[DirtDonk]

Thanks for the pics!
Measurements seem consistent with our 3.5" lift, or a slightly settled in 4.5" lift.
My vote is with the more popular 3.5, but it might depend on what size tires the previous owner installed. We might be able to narrow it down by the part numbers on the Rancho 9000 shocks.

Pinion does look low from this angle, so shims are called for it looks to me. Small end forward...
Pretty typical of this amount of lift in fact. As mentioned by rocknhorse earlier, the standard 6° shims would most likely to the trick.
Here are ours: WH 1188 Tapered 6° Leaf Spring Shims Made from steel and include longer center bolts so they can be bolted to the pack. Rather than just sandwiched in-between.

The desired result is a rear pinion angle that aims up to about 1 or 1.5 degrees below the centerline of the driveshaft.
Assuming yours is still equipped with a driveshaft utilizing a double-cardan setup at the transfer case?

Paul

 

[Madgyver]

https://www.dropbox.com/scl/fi/6cxs...1718.jpg?rlkey=bl900xf7pwlj1e9c229gy5te6&dl=0

In this pic, pinion angle looks good. No need for a wedge. My opinion.

 

[DirtDonk]

Best way would be to measure then. Looked a little low to me.
The bubble level doesn't really tell us anything in the picture, but if you can get an accurate angle "difference" between the driveshaft and the pinion shaft, that would tell the tale.

Paul