Barfly

I finally made it to the Big Junk Yard in the city and got a look at a differential in another Dakota.

I've been convinced that I have a Chrysler 8.25 in my truck based on some pictures from the net.

After seeing another one up close I now am wondering. The main thing that throws me is the lack of a Plug on the cover. He is a picture of mine:



Can any one tell by this cover what I have (click the pic it gets bigger)
Thank you
Joe.

1966sportfury

you have a 10mbolt 8&1/4
the gears that are availible for the 3rd member are 2.71, 2.94, 3.21, 3.55, 3.90, 4.10, and 4.56
you im sure have the 3.21, using the calculations i posted a wile back.
there should be a drain plug on the front of the 3rd member,

Barfly

Thanks bud,
I lifted up the wheels and confirmed by rotation its what I thought to be a 2.76 ratio but 2.71 is close so given that was what was available I bet that's it.

Now the good news, moments ago I sealed the deal on a complete 8.25" Dakota rear end with 3.55 gears for $150. Bad news is it has 6 bolt hubs which means I will also need the wheels for another $50....... I'm sure that's not all

Thanks man
Joe.

78D200

You may want to look into seeing if you can get shafts that are the same 5 lug that you have now for that 8.25. Also take some measurements and see if the brakes will swap over. If they will, then shafts are all you need and havine a set made up out of 1541H material is pretty cheap and will be ~25% stronger than stock.

1966sportfury

wile you use that rear end go to local junk yard and look for the ford 8.8 rear end, mustangs, ranger, they are a good rear end and stronger than the 8.25,

78D200

5 on 4.5 bolt pattern, disc brakes, sway bar and half of them came with a rebuildable LS. All you need is a new yoke to bolt it up to your driveshaft and a proportioning valve. Only thing you need to watch for is the WMS to WMS width.

This is a very common swap on Jeep YJs and TJs.

Barfly

My son and I jacked up the truck and slid the new rear end under just to see how things lined up. All looks pretty good except I noticed the yokes are completely different. Knowing this I am starting to wonder what will be the best route to take.

1. Pull the 3.55 gears from the new rear end and hope they fit into the old rear end.

2. Go ahead with the complete rear end replacement and worry about replacing the yoke or jury rigging the drive shaft.

Here is a picture of the two yokes.



Any idea's ?
Thank you
Joe.

Silverick

I replaced the 8 3/4 open rear end with a Sure Grip in my Fury a number of years ago and had a similar issue.
The thing that I did, was replaced the drive shaft to match the new yoke. It was the simple fix and I was able to retain the larger universal joints.

MercuryDon

They are what we in the parts business called conversion U-joints Precision makes a number of differant ones. Try a good parts house they will need to know what the yokes came out of or the measurements and type of joint( ie.inside or outide snap rings if any). Yokes can have differant lengths too so make sure they are the same length or your drive shaft will be the wrong length with the new yoke.

Barfly

Hey guys, this thread is from back in July '10 we ended up changing out the gears from one rear end to the other and all went together well. We did have trouble tightening the pinion nut, but it's all done now and the truck goes down the road with 3.55 gears.

Joe.

78D200

When setting up gears, I use a monkey wrench on the yoke, have it dig into the ground and torque down the pinion nut.