Rear differential question

[s'ko]

I am almost done with my lift. The BRAT looks mean. It’s sitting on 225/75/16 or 29x8.8/16. The back bumper sits 39 inches off of the ground. But the center differential is about 10 inches.

 

I used 5X2 square tubing to make the lift. The diff hanger I welded a piece of metal plate and dropped it 5 inches. What else can do to get more clearance in the middle?

 

Here is a really bad cell phone camera picture of the wheel.

 

BW

[Scott in Bellingham]

pictures, on the EA81 you dont want more then a 1" over stock angle on those axles its the weak link ,in my opinion

[s'ko]

yeah I forgot my camera at work. I was jumping like an idiot last night when I got the wheels to fit.

 

The lift blocks for the rear are the same height as the front blocks. I might take them down and lower chop it by an inch. That should move things up.

 

I did the rear diff hanger like this

http://i81.photobucket.com/albums/j208/boswan/diffhanger.jpg

 

I also noticed that it's not all bolted up tightly. I will probably get about and inch or two when it's all secure. Will take better pictures this weekend.

 

BW

[Sweet82]

What else can do to get more clearance in the middle?

 

 

Put more air in your tires!

[s'ko]

Put more air in your tires!

 

How about helium?? Then get some helium ballast tanks and maybe hook up a prop into the rear drive shaft.

 

It's will be a ZEpbrat....

 

Darn.. .to bad Zap didn't say that then I could call it a Zapplin.

[Reveeen]

I'm building a lift and the same question has been bothering me.

 

Checking this out here:

http://alliedarmament.homestead.com/Comparison.html

(3rd/4th set of pictures from the top)

It would seem that Allied is not moving the differential down.

Now, I'm not saying you shouldn't move the differential, but maybe not quite as much as your lift, say 3" (on a 5" lift), giving you 12" of ground clearence?

I guess it would all depend:

1) on how the axle angles look

2) on how much horsepower you are intending on trying to put through your rear dif./axles.

[Scott in Bellingham]

I'm building a lift and the same question has been bothering me.

 

Checking this out here:

http://alliedarmament.homestead.com/Comparison.html

(3rd/4th set of pictures from the top)

It would seem that Allied is not moving the differential down.

Now, I'm not saying you shouldn't move the differential, but maybe not quite as much as your lift, say 3" (on a 5" lift), giving you 12" of ground clearence?

I guess it would all depend:

1) on how the axle angles look

2) on how much horsepower you are intending on trying to put through your rear dif./axles.

 

the only axle failure I have experianced was with 3" difference , that was a 3" lift on the rear of a EA82 with no diff drop that was on the Blue Bomber sand car , i woldnt go past 2" difference on EA82 and 1" difference on a EA81 , when I saw the Allied wagon at wcss7 it had many split axle boots on the rear

[86BRATMAN]

Some people have used the longer ea82 axles in ea81 cars to help with the breakage problem, might want to look into that.

[Phizinza]

Some people have used the longer ea82 axles in ea81 cars to help with the breakage problem, might want to look into that.

I think you mean using the EA82 DOJ cups on EA81 axles in an EA81.

 

How much angle are on your axles?

As in, what is the difference in inchs between your hub stubs and the diff stubs? I reckon 2 to 2.5" is good, but have never measured mine..

 

Also you'll notice if you bring the back of the diff up your just putting more angle on your axles and propshaft, without getting more clearence because the front of the diff doesn't go up either, unles you do the spline crank on the torsion bar and only use like 3" lift blocks in the rear.

[86BRATMAN]

Could have been what I read. It's been a while since I looked into the lift stuff...

[Reveeen]

the only axle failure I have experianced was with 3" difference , that was a 3" lift on the rear of a EA82 with no diff drop that was on the Blue Bomber sand car , i woldnt go past 2" difference on EA82 and 1" difference on a EA81 , when I saw the Allied wagon at wcss7 it had many split axle boots on the rear

 

I *think* it would almost go, without saying, that ANY suspension mod on a 10+ year old vehicle with "booted" axles (half shafts) would include rebuilding/replacing those boots. I know I expect to do mine while in there.

 

I *think* too I did mention horsepower, the standard EA81/2 horsepower isn't going to break things in a hurry, but if doubled (or tripled) the more extreme angles will.

 

I am concerned a bit about driveshaft angles, but figure eyeing it up as I go will keep me within reasonable.

 

We must remember too that extreme angles will create frictional losses and most of us are not starting with a whole lot of power to begin with.

[s'ko]

I *think* it would almost go, without saying, that ANY suspension mod on a 10+ year old vehicle with "booted" axles (half shafts) would include rebuilding/replacing those boots. I know I expect to do mine while in there.

 

I *think* too I did mention horsepower, the standard EA81/2 horsepower isn't going to break things in a hurry, but if doubled (or tripled) the more extreme angles will.

 

I am concerned a bit about driveshaft angles, but figure eyeing it up as I go will keep me within reasonable.

 

We must remember too that extreme angles will create frictional losses and most of us are not starting with a whole lot of power to begin with.

 

I have an EJ18. So there is a HP gain from the stock EA81 but nothing to about.

 

I think I am going to drop the lift bits and trim the lift block by an inch. That should give me a bit more diff height.

 

Thanks for all of the input.

 

BW