Best options for a rear end swap

[gordsguard]

I was hoping to use the stock rear end. I still may use it but I'd like to have an alternative ready to go. What's the best fit for my 48 1/2 ton? Needs to have original bolt pattern. Gear ratio isn't a huge deal as I'm running an OD trans. Just want something that's as close to "bolt in" as possible and has an E-brake.

Looking forward to your input. Thanks

Nathan

[Dave72dt]

Several have been recommending the use of a Jeep Cherokee. Do a search for Jeep, should bring up several threads.

[austinsailor]

It might be good to hear why you're considering changing, especially if you're not needing another ratio.

Is yours about to die? There are plenty of originals around. Otherwise I can't see why you'd want to go to the work.

[NiftyFifty]

I don't think any other rear diff is a direct bolt in, but yes the jeep axles come as close as the original in length etc. My 50 is a 1 ton and I swapped the original for a 93 Jeep YJ rear diff and all it really needed was the spring perches moved to make it the right angle for the truck...but being a 1 ton I had a big HD diff, different from the 1/2 tons and my driveshaft was no longer long enough...I've heard in the 1/2 tons it works fine with the changing of the rear U-joint to a "conversion" joint.

I did the swap because the original was impossible to get brake parts for, I didn't want the ugly 6 bolt steel rims and I also wanted a better updated brake system and rear park brake....if you remove the stock trans then you have to have something in the rear end for a parking brake system, as you no longer have a shaft brake

Edited March 27, 2011 by 4mula-dlx

[41/53dodges]

i converted the 53' to the cherokee rear end, mostly for brakes, but the u-joints are the EXACT same for the 1/2 tonners, and the ratio comes out to almost a perfect +25% i wonder, how far back have PH owners done this?

[gordsguard]

I'm thinking mine has had a long hard life. There appears to be a large amount of play in the ring and pinion. Also I'd like an e brake. I'm planning on opening the old one up and seeing how it looks inside. Maybe I'll use it....but I still want a backup plan.

Nathan

[Dennis_MN]

The Jeep Grand Cheokee is supposed to be a bolt in fit, from what I've read in previous threads. I bought one with disk brakes so now I'll have disks on all four wheels. This is a Dana 35 with 3.73 ratio and it does have e-brakes inside the rotors although I don't plan on using them. I'm about one month away from bolting it in.

Dennis

[NiftyFifty]

  Dennis_MN said:

The Jeep Grand Cheokee is supposed to be a bolt in fit, from what I've read in previous threads. I bought one with disk brakes so now I'll have disks on all four wheels. This is a Dana 35 with 3.73 ratio and it does have e-brakes inside the rotors although I don't plan on using them. I'm about one month away from bolting it in.

Dennis

I have a hard time beleiving the perches are in the exact right spot??? or at the right angle from what the old diff was???

The u-joints are probably the same in a 1/2 ton...I've never had a chance to compare the two...I'm coming from the 1 ton driveshaft where they are not the same, but NAPA found me a conversion one quite easily

[Dennis_MN]

You are right, I picked up spring perches from Northern Hydralics and right now I'm grinding off all of the old scars from the cutting torch where the spring perches were removed. I have some measuring to do, and the angle to figure, then I'll have them welded and then it will be ready to slip into place. I'm doing it at a friends shop and I'm figuring on a 1/2 day's work.

There was unbelievable number of brackets to cut off the the Jeep axle. I found where you could order a new one with out brackets, just under a $1000

[NiftyFifty]

  Dennis_MN said:

You are right, I picked up spring perches from Northern Hydralics and right now I'm grinding off all of the old scars from the cutting torch where the spring perches were removed. I have some measuring to do, and the angle to figure, then I'll have them welded and then it will be ready to slip into place. I'm doing it at a friends shop and I'm figuring on a 1/2 day's work.

There was unbelievable number of brackets to cut off the the Jeep axle. I found where you could order a new one with out brackets, just under a $1000

WHOA!!! lol....you should have kept those shock mounts...they work just fine if you make some easy mounts and do a bit more figuring...I'm very glad I didn't cut mine off....I had to have them to pass the safety inspection up here to get it licensed.....

As for the cutting and re-welding the perches...yer bang on...about 1/2 day and your done...the measuring was easy and the gauge about $20 from most hardware stores... I do somewhat wish I would have found a rear diff with disc, but calipers would have been pricey

[Dozerman51]

You can swap in any Mopar 8&1/4" third member 1940's to late 50's into your truck. Chrysler's and Desoto's had the lower ratio's. 3.91 and 3.73. Spline count changed around 51-52 so use the axle shafts also. Direct bolt in. Did the swap on my 41 Military 4x4. Less work than that Cherokee swap. Hope this helps.

[Dennis_MN]

I just finished removing all of the slag from cutting off the brackets from that Jeep Axle. When I had the shop change the seals and replace the bad bearings, I had him cut all of the brackets with a torch.

I bought a new grinder from Northern Hydralics and some flap type sanding disks and went to work to remove all of the left over metal. Took about two hours and now I'm ready to clean it and paint it with POR-15

I alternated sides to reduce the heat effect of the grinding

[Merle Coggins]

Lookin' good Dennis. By the way, you wouldn't get away with that in my shops. No PPE!!! Shame on you. We require safety glasses and a face shield when grinding, plus hearing protection and gloves are highly recommended.

Merle

[NiftyFifty]

For years I have been a renegarde as well....no face mask or hearing protection...now I have ear problems and I was blind my whole life so that's no issue, but I caught a spark in the eye last year working on my 50 and that was enough to convince me to have safety gear all over my shop so it's not a chore to find..it's right where you need it....lookin good...spray down the axle with a rockerguard style paint and you will never know anyone ever touched it with a grinder...

[Dave72dt]

You'll want to have the spring pads welded on before painting it. Check pinion angle before locking it down with the full weight of the vehicle on it. I prefer to use a regular grinding wheel on the heavy material and finish with a flap. More economical. A taller bench to work off of will help on the back. I see you were bending over to grind. You may want to remove the heavier residual valve in the rear brake line and go to the lighter one, same as the fronts now that you have discs all around.

Probably already know all that stuff anyway. Looked like you were enjoying the work and that's what counts.

[Don Coatney]

  Dave72dt said:

A taller bench to work off of will help on the back. I see you were bending over to grind.

I agree with that. At my age it would kill my back to work at an uncomfortable height. I used an old shipping crate when I did my differential.

[John-T-53]

I have read somewhere that arc welding on the axle housing with the diff installed is not adviseable, since there's a chance the gears or bearings could be damaged, no matter where you put the ground lead.

Is this true?

[Dave72dt]

If you put the ground clamp on the pinion yoke and welded on the axle tube, I'd say yes. Properly prepped weld area with the ground clamped on a bright clean area next to it should create no problems. Electricity always takes the path of least resistance.

[NiftyFifty]

  John-T-53 said:

I have read somewhere that arc welding on the axle housing with the diff installed is not adviseable, since there's a chance the gears or bearings could be damaged, no matter where you put the ground lead.

Is this true?

I would say it's a pretty thin chance...I guess it could happen, but I found it easier to clean off a portion of the tube and lock vicegrips to that then hook up my ground....then again I didn't have the yoke on at the time..

[cwcars88]

I agree with John T, NEVER weld threw a bearing. That is one thing that I did remember my welding instruct-er saying.

[dodgebrice]

The key word is through. If you place your ground next to the spot your welding you will be fine. If you have your housing apart to clean or repair that is the best time to do welding repair (changes) but is not necessary.