* I am starting this thread now, but will finish it this evening.*
This is a brief write up on installing a Chrysler 8.25 from a Jeep Cherokee XJ (not grand Cherokee). The Chrysler 8.25 was available 91-01 of XJ production along with the Dana 35. The 8.25 is a stronger axle than the D35. According to the net, mid '96 they went from 27 spline to 29 spline shafts. Either would be fine for an Eagle, but I chose 29 spline because I just wanted the stronger of the two since my engine is a little built and I do some off roading. The width is almost identical to the AMC 15. The highest gear ratio you'll find is a 3.07 and is usually found in 4.0l 5 speed equipped XJ's. The 4 speed automatics came with 3.55's unless they have the tow package and then will most likely have 3.73.
You can identify a 8.25 vs a Dana 35 by the cover. The 8.25 is more flat top and bottom and the D35 is rounder.
(http://www.cherokeetalk.com/forum/attachments/f20/4728d1312516746-stock-dana-44-diffguardtype.jpg)
Here's some comparisons I got from this site http://www.naxja.org/forum/showthread.php?t=1007507
Dana 35 non c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 84-89
Dana 35 c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 90-01
Chrysler 8.25 - 27 spline, 1.17" diameter shafts, 8.25" ring gear, 3" axle tube - used 91-96
Chrysler 8.25 - 29 spline, 1.21" diameter shafts, 8.25" ring gear, 3" axle tube - used 97-01
Dana 44 non c-clip - 30 spline, 1.31" diameter shafts, 8.5" ring gear, 2.75" axle tube - used 87-89 on some(not all) XJs equipped with towing package.
Use common sense. Jack up the car and use jackstands. Wear safety glasses and other appropriate safety gear.
Step one is removing your old axle. I would recommend spraying some PB Blaster or other rust penetrator on nuts and bolts prior to doing the work. Put the jack under the differential and jack it up to take a little of the sag out of the rear springs. Remove the driveshaft from the pinion yoke. You might want to wrap the ujoint caps with electrical tape to keep them from falling off while they are unbolted. Remove the hard brake line that comes from the car to the flexible hose going to the rear. I stuck a golf tee in the metal line to keep it from dripping. Remove vent hose. Remove brake drums and brake shoes to remove parking brake cables. You will use the cables on the new axle. I found it easier to also remove the cables from the bracket where they connect to the single cable. This allows you to pull the cables off the bracket that is attached to the rear shoe. Removing the cables from the backing plate can be a nuisance. There are 3 prongs you need to push in so that it comes out of the plate. Remove the nuts for the shock absorbers and remove the shocks from the rear axle. Now, your ready to take the nuts off of the ubolts that attach the housing to the leaf springs. The axle will be unstable on the jack, so be careful. I prefer to use a transmission jack that I got from Harbor Freight. Move axle from under car.
The shock mounts need to be cut off of the 8.25. A torch or plasma cutter would be great, but I used a 4 1/2" grinder. Be careful not to cut into the axle tubes. You will need to either reuse the metal brake lines from the Eagle's Model 15 or flip the lines on the 8.25 since the flexible line is on the left side on the XJ vs the ride side on the Eagle. You can try to cut off the shock mounts from the Eagle axle and attach them now or modify the 8.25 brackets and weld them on. I choose to weld them on after the axle is in, so that I weld them in the right spot.
Now your ready to install the 8.25. You'll need the u bolts and plates from the XJ. Lift it into place allowing the spring centering bolts to fit into the leaf spring pad and install the u bolts. Now install the flexible brake line to the hard line. You'll have to figure out a way to mount the brake hose. I made a plate that bolts where there are 2 bolts in the 8.25. (pics later) Remove the brake drums and rear shoes and install the Eagle parking brake cables into the parking brake bracket. You have to pull the spring back and slip the cable into the slot. Now you're ready to weld the shock absorber brackets if you haven't already. If you use the Eagle brackets, you'll have to cut out a little bit more of the radius to match the larger 8.25 axle tubes. The first one I did, I used the Eagle bracket. The second one I modified the 8.25 brackets because I wanted to keep the other axle to be ready to bolt in to another Eagle. You can reference the old brackets on the Model 15 or just set the brackets into the shocks and tack them into place once you have them where you want them.
Here's what it looks like when removed from the axle:
(http://img.photobucket.com/albums/v637/svoman2300/photobucket-30358-1399997456780_zpse772e564.jpg) (http://smg.photobucket.com/user/svoman2300/media/photobucket-30358-1399997456780_zpse772e564.jpg.html)
After my modification:
(http://img.photobucket.com/albums/v637/svoman2300/photobucket-22471-1399997506265_zps90d26e51.jpg) (http://smg.photobucket.com/user/svoman2300/media/photobucket-22471-1399997506265_zps90d26e51.jpg.html)
AMC Model 15 vs Chrysler 8.25
(http://img.photobucket.com/albums/v637/svoman2300/Eagleaxleswap5.jpg) (http://smg.photobucket.com/user/svoman2300/media/Eagleaxleswap5.jpg.html)
(http://img.photobucket.com/albums/v637/svoman2300/Eagleaxleswap1.jpg) (http://smg.photobucket.com/user/svoman2300/media/Eagleaxleswap1.jpg.html)
(http://img.photobucket.com/albums/v637/svoman2300/Eagleaxleswap3.jpg) (http://smg.photobucket.com/user/svoman2300/media/Eagleaxleswap3.jpg.html)
I'll finish later, got to get back to work. 8)
RESERVED
I did mine about 6 months ago but haven't been able to do the shock mounts yet. This vertigo BS has me ready to get rid of all my vehicles and mobile home just so I can live at my cabin.
Quote from: carnuck on May 13, 2014, 02:11:45 PM
I did mine about 6 months ago but haven't been able to do the shock mounts yet. This vertigo BS has me ready to get rid of all my vehicles and mobile home just so I can live at my cabin.
Not to sidetrack this thread, but I know where you're coming from and feel for you. I've been having vertigo issues the last couple of weeks. I think it is from the NSAIDs I've been taking for pain. I stopped taking any meds about 3 days ago and it's getting better. I don't know if I could take it for 6 months. My head was spinning every time I got up from laying under the car.
Intresting, I'm looking forward to the rest of the write up
I assume width is the same? If so I suppose one could do this swap into a 2wd amc car as well? For example a spirit with a beefed up v8 and still an amc 15 ?
In addition did you match gear ratios with the front axle before installing, or did you already do the front to match the back?
Did you have to do anything with the driveshaft yoke, or is it the same?
You might be gonna cover all of this later anyway, if so sorry
I didn't do anything with my driveshaft, but it should be shortened about an inch or a longer slipjoint used. Ubolts are wider and spring plates are different too (grab the XJ ones. I had some leftover thick steel ones from a Dana 60 I swapped that were perfect) My Ubolts are thicker too. They were made for my front axle of my J4000 that I didn't get to finish because I rolled the truck.
Quote from: Amc1320 on May 13, 2014, 05:42:07 PM
Intresting, I'm looking forward to the rest of the write up
I assume width is the same? If so I suppose one could do this swap into a 2wd amc car as well? For example a spirit with a beefed up v8 and still an amc 15 ?
Width is the same. It might be .1" narrower. For 2wd you'll have to remove the leaf spring pads and weld them under the axle.
In addition did you match gear ratios with the front axle before installing, or did you already do the front to match the back?
Not yet. I'll do that in the future. Until then, it's a 2wd car.
Did you have to do anything with the driveshaft yoke, or is it the same?
When I originally installed the first one, I didn't do anything with the stock driveshaft. It bolts up to the 8.25 yoke. But like Carnuck mentioned, it probably might need to be shortened a hair.
You might be gonna cover all of this later anyway, if so sorry
The axle is 3" wider than 2wd AMC cars. Unless you use FWD (like Dodge Caravan for example) offset rims in the back, the tires WILL hit the fenderwells with the axle set as SUA (spring under axle)
Any updates to this? Been looking for a D35 but might have to go up to the 8.25...just that cutting the driveshaft now AND later doesn't seem appealing in the least to me.
D35 requires no cutting.
Does the 8.25 require cutting? From looking around some people decide to cut while others don't. I'm going to have to cut when I put in the AW4, so I don't want to have to cut twice.
I might lift the rear end with a couple of XJ add-leafs. That might negate the need to cut right away.
I didn't cut my driveshaft when I installed the first 8.25 and drove it for 4 years without any issues.
If you aren't sagging, you shouldn't need to cut.
I'm sagging a bit but my rear shocks can be inflated, but when I do the swap I'm going to put in an XJ leaf or 2 so I can stiffen up the rear end.
The driveshaft will have to be cut for the xj drivetrain I'm putting in though.
Looks like the 8.25 might be the winner.
The main XJ leaf with the eyes cut off put in #2 position of the Eagle pack lifts you to original Eagle height ( even with the air shocks fully pumped up) If you add 2 of them, you won't be happy with the truck-like ride (and NOT SUV either!) Don't forget you need bigger Ubolts and the spring plates from the XJ as well. I used Dana 60 plates on mine.
hoping this thread isn't totally dead - i'm about to swap in an 8.25 to my eagle. i looked in the front axle thread as well but didn't find a solid answer - my gearing is 3.55 - 39 and 11 tooth count ring/pinion which equals 3.54545454545454 and on...
there seems to be some contradictory info in that thread - conclusively the 2.73 carrier (which i have) will support a 3.54 ratio but maybe not 3.55? are 3.54 and 3.55 close enough to run together, especially considering the viscous coupler of the 229 i am running?
what did you do or are you still a 2wd eagle?
thanks
I believe 3.54 and 3.55 are close enough together that it will be fine.
Quote from: kajsdf on September 11, 2014, 09:28:54 PM
hoping this thread isn't totally dead - i'm about to swap in an 8.25 to my eagle. i looked in the front axle thread as well but didn't find a solid answer - my gearing is 3.55 - 39 and 11 tooth count ring/pinion which equals 3.54545454545454 and on...
there seems to be some contradictory info in that thread - conclusively the 2.73 carrier (which i have) will support a 3.54 ratio but maybe not 3.55? are 3.54 and 3.55 close enough to run together, especially considering the viscous coupler of the 229 i am running?
what did you do or are you still a 2wd eagle?
thanks
3.54's will work fine. It's such a small difference. I ordered some 3.54 gears from Rock Auto. They just arrived today, but I'm out of town for work and will have them installed when I get back home. I'm meeting with a guy this weekend in Billings, MT who had 3.73's installed in his Eagle Dana 30 and said it wasn't too difficult for his mechanic. I'll find out the specifics.
You just need gears from a low pinion diff. The XJ isn't so you need them from a Grand Cherokee or something. I think the rule of thumb is 1% on the difference front to rear and it's better to be tall in front (PULLS you through the corner) I wish I had taken a pic of the gears we took out of my son's Grand Cherokee monday.
Quote from: carnuck on September 12, 2014, 01:22:23 AM
You just need gears from a low pinion diff. The XJ isn't so you need them from a Grand Cherokee or something. I think the rule of thumb is 1% on the difference front to rear and it's better to be tall in front (PULLS you through the corner) I wish I had taken a pic of the gears we took out of my son's Grand Cherokee monday.
Just to help clarify , it needs to be a long low pinion gear set. Grand Cherokees are a mix of short and long low pinion. XJ's came with low and high pinion depending on year but are all short pinion. Jeep CJs came with long low pinion D30s.
My blue SX4 was a 3.07 iron duke from the factory. The previous owner swapped the iron duke for an I6. The I6 had 2.35 gears from the factory and he must have mixed up which front diff was which during install. He drove it for years and I drove it for awhile assuming they matched. When I took it apart I confirmed that they were actually much different.
I checked the VC and it was still ok. It allows a lot of slip before it slowly engages, so it is forgiving.
If no damage occurred from years of driving with 3.07 in the rear and 2.35 in the front, I highly doubt your car will care about 3.55 vs 3.54.
Are you sure you don't have the NP128? It does the same thing as the NP129, but no viscous coupler.
It was a NP129 and still in good shape. The 3.07 rear surprised me the most, since that isn't common in an original SR4 Iron Duke. I was counting on it having 3.54 all the way around and I checked it several times before I believed it.
This experience pushes me further to use the 242. The Eagle is still quite capable with an open diff like the NP128, those with a burned out VC, or the 242 in full time. In slippery conditions I will value the fully locked diff instead of a VC.
Quote from: captspillane on September 15, 2014, 06:24:55 AM
In slippery conditions I will value the fully locked diff instead of a VC.
In the beginning of the year, we had a few inches of snow, which is rather rare. However, it quickly turned to a sheet of ice on the roads. There was one hill where people were struggling to get up. With my 242 in fulltime, my Eagle was struggling to get up. Put it in part time and got right up. I have no idea how well it would have done with a case with a VC, though.
I know in the full size rigs that when the VC pukes it's "guts" that "oil" (really liquid silicate, ie: sand) destroys the bearings, etc in short order.
So I gutted my XJ, took off the rear axle and noticed that it's a 8.25. Any idea if I'll have any issues with the full XJ drivetrain swap? Using the AW4/NP242 combo. If there is going to be an issue I'm going to have to search for a D35 really fast.
What issues are you expecting? I have the AW4/NP242/8.25 without any issues.
driveshaft fitment.
It's a slightly longer input, but I used the original driveshaft. It comes close to bottoming out now but it's okay on road. Lifting more will cure it. You need the 8.25 U bolts and plates for the springs. You will also need to weld on shock mounts.
Quote from: Nightpath on October 18, 2014, 10:46:32 PM
driveshaft fitment.
Honestly, with all the work you will be doing for the swap, getting a drive shaft to fit should be the least of your worries.
Everything is going swimmingly so far ;)
My next project is putting a 8.25 in my Comanche.