[my91jeepyj]

I recently destroyed my Dana 35 rear end. The parts to replace the whole set up would have run me nearly 500 to 600 dollars (that's including the special tools I would need to set up the gears correctly). Fortunately for me I have access to this site and was inspired to upgrade my rear end with an 8.8. This is my attempt.

Surprisingly, it wasn't hard to find an 8.8. My local salvage yard had several ford explorers. Fortunately for me, I found one with the correct ratio out of a 97 for $240.


The boys did a good job of taking it out for me. They left the brake lines intact as I requested. This should no doubt save me money.


Before getting started, I decided to double check the gears myself for wear, and for the correct ratio. I was surprised to see just how beefy the 8.8 is! It's no wonder people are putting these in their jeeps. Everything was in good shape.


After verifying that everything was ok, I got started on cutting the sway bar brackets off. I started with an electric cutting wheel, but soon found that the die grinder, being smaller in diameter, made a closer cut around the contour of the axle.


Take your time and do not cut too close and damage the axle. A small amount of metal is nothing to grind down. You can always take away, however it's harder to put back.


Grind it smooth.




I got to measuring, and at first it looked as though the spring perches were about 1" over all closer together than my existing set up. I measured a few more times and found other wise. When I take my old axle out I will verify this again before cutting the perches off.

That's enough for today. Tomorrow I plan to take my old axle out and cut off the shock and sway bar mounts and weld them onto my new axle. I plan on getting new U-bolts but I'm going to try and reuse the plates.

I needed new brakes anyhow so I'm not going to add that to the cost of this project. I plan on rebuilding the calipers, which by the way are a lot smaller than I had previously thought they would be, and get new e-brake shoes. A little chassis saver I have left over from a recent project should ensure a good, rust free, future for my new rear end.

One thing I found that worries me. While measuring, I found that the punkin is an inch or two further towards the passenger side than my current axle. I'm wondering if this will cause me vibration problems. I guess I'll find out soon enough.

[Anticanman]

Looks good!! You may have to cut off the old perches and reweld them a little closer or get a new set of perches if you damage the stock ones. There is sometimes a little bit of vibration in the rear driveshaft but with the control of settin the pinion angle you should be able to eliminate the vibrations before they start. With large lifts, the SYE and new driveshaft are necessary but in your case, the pinion nose is a bit longer and your driveshaft may need some slight shortening after the adapter is fitted. There are a thousand "pros" to every little speedbump in the install process of this axle.

[my91jeepyj]

As of now, I don't plan on moving the perches. Now if i take my axle off and measure it again and find that I need to move them, are you telling me not to put the angle back just as it is? What is the optimum performance angle that I need to achieve?

[Soon2AdjustYou]

Well done so far...subscribed

[lutzke21]

Originally Posted by my91jeepyj

As of now, I don't plan on moving the perches. Now if i take my axle off and measure it again and find that I need to move them, are you telling me not to put the angle back just as it is? What is the optimum performance angle that I need to achieve?

I just tried to ensure my pinion/d.s. were lined up when the jeep is level with the weight on the wheels. That and compared it to the D35 to see if it was if it was in the same ballpark and compared it to what others had with comparable lift/tire size combinations. Your angle won't be the same because your jeep is different then everyone else's, even with the same lift/tire size. I'd have to check, but I think I was around 17°. I'll try to remember to look it up tomorrow.

[Mean Max]

I've done a lot of 8.8 swaps into YJs, and you MUST move the perches. I have used the $25 Warrior Products brand perches and they fit the 8.8 axle tube diameter perfectly.

You should not use anyone's pinion angle dimensions, set yours where it should be for your application. They will all be different from vehicle to vehicle.

With a stock slip yoke & driveshaft arrangement, both u-joints should have the same amount of deflection while sitting with the vehicle's weight on the axles.

Max

['92 vegas YJ]

Originally Posted by Mean Max

I've done a lot of 8.8 swaps into YJs, and you MUST move the perches. I have used the $25 Warrior Products brand perches and they fit the 8.8 axle tube diameter perfectly.

You should not use anyone's pinion angle dimensions, set yours where it should be for your application. They will all be different from vehicle to vehicle.

With a stock slip yoke & driveshaft arrangement, both u-joints should have the same amount of deflection while sitting with the vehicle's weight on the axles.

Max

X2 to everything Max said. you must cut and reweld perches and every vehicle is different so you need to set your pinion angle according to your Jeep

[jason280]

As Max mentioned, you will have to cut and move the spring perches. I know some people "pinch" their factory springs in to fit, but this is not the correct way to do things. You already have the axle out, so there is no reason you can't move the perches out. They don't have to go far, something like 5/8 or 3/4" (if I remember correctly, its been a couple of years since I did my last), but its not a difficult job.

[my91jeepyj]

Alas! You were right. I had to cut off the spring perches and move them out.

Before doing anything, I had to make sure I got the angle correct. First I put a level on the leaf spring perch of the 8.8.


Next I checked the pinion angle.



After measuring the D35, I found that they were both 80 deg offset from the spring perch.


I am building on a tight budget. I had just rebuilt my engine and Monstalined the inside; I am about tapped out here. I decided to save myself some money and reuse all the brackets and perches from the Dana35.


After verifying my angle and measuring for my spring perch location, and mocking up my shock brackets and sway bar bracket, it was time to cut off the 8.8 perches. They were on there pretty darn good. I hope the new welds are at least half that strong.


My brother helped me weld the old brackets on. I admit they are not the best welds, and another thing to keep in mind here is that I don't go wheeling. My jeep is for cruising and fishing trips and looking pretty in. If I had any intentions on wheeling I would no doubt have put a stronger bracket set on.


My spring perch location. I am not the best at taking measurements, but from what I found, the old 8.8 perch holes were nearly 1" (total) too short and needed to be moved out. I moved them out equally, 1/2 inch on both sides. On top of that I noticed that the perch holes on the 8.8 are too large for the leaf spring pin, which is 1/2" in diameter. Also the perches themselves were, if I remember correctly, 1/2" inch longer over all. Upon welding the old perches to the axle, I noticed the d35 perches were slightly rounded to match the contour of the leaf spring. With all of those factors in play, I decided to reuse the old d35 leaf spring perches.


After a lot of measureing and remeasuring, I found the 8.8 pinion to be at nearly the exact angle as the d35, only slightly taller (roughly 3/4") The over all length of the of the pinion seemed to me to be the same, with the exception of the pinion plate setup.

Now one other thing to mention here. I was upset to find out that the 8.8 pumkin is further to the right on the axle than the d35. I figured it would lead to vibration issues and was surprised to hear it didn't. Well, what I found in my extensive measuring is that the D35 is slightly to the left of the T.C output (at least in my rig). So the offset of the 8.8 simply puts that factory offset to the right of the T.C. output instead of the left. So now it's clear to me why there seems to be no vibration issues with others.