Ugh. So frustrating. What is my gear ratio? Can’t find tags on the front or back. Can’t spin the wheel because the shaft doesn’t spin. Equipment identification sticker under hood says “DMD 3.5 Axle Ratio”. Does that mean 3.55? I can get a 3.55 for $350.
Count the number of bolts used to mount the differential and if the replacement has the same number, it should fit. and 3.5 is close enough to 3.55 and the stamp may have been truncated to one decimal place so they would be the same.
Well yeah. If if don’t fit don’t force it. Get a bigger hammer.
Curious, could instock simply replace the third member unit, and keep the existing axel housing/differential housing, and maybe even the existing two rear axel shafts?
@GeorgeSanJose I would not suggest that, since Dodge pick ups use that wonderful axle system where the inner race of the outer bearing is the axle shaft itself. In fact it might be a good idea to at least have a look at the axle shafts of a used rear end to see if they need to be replaced. The shafts and bearings are available aftermarket for a lot less than the dealer gets.
The axle surface is the bearing race? Oh my.
hmm … well, I guess this configuration isn’t unheard of. That’s the way it is done on my bicycle, not on the wheels but on the bottom bracket, the axle that connects the two crank arms, its surface is one of the bearing races.
And come to think of it, that configuration causes me no end of grief! Next time I have to fix it, I’m switching to a sealed bearing unit, where both races are separate parts from the axle.
“The axle surface is the bearing race? Oh my.”
A lot of GM axles do the exact same thing. It’s not unique to Dodge or a lot of solid axle designs. I agree with several above. It’s easier and cheaper to swap out the whole rear-end, housing and all, with a salvaged unit. It’ll be much cheaper than a rebuild.
Well… I talked to a shop and he ballparked it at $600 to $700 in labor. Plus $350 for the rear end. Plus $100 for other parts. Plus $100 for the tow. Plus tax. Basically it’s $1300 minimum. And it could easily be more if there are problems with the brake lines or whatever.
I’m tempted to try it myself. But in reality it won’t get done in a weekend. It’s one of those things. I’m sure I’ll have tons of questions. Additional problems will come up and the project will grow. It’ll take a few weeks. The parts are not free either.
This truck is scrap metal.
if it is scrap metal, you have nothing to lose…just a small investment in a few parts. give it a whirl. you’ll learn a lot. just spend more time reassessing nothing else is amiss.
I hear ya. A few years ago, I would have done that. Now? How do I explain to my wife that I’m blowing $500 on it and it will take up all my time and maybe get fixed eventually? Even if it does get fixed, it is still a '97 with 160,000 miles. I have already spent a week on it and I have learned a lot thanks to everybody here.
Once you get the old axle off the truck it could be a piece of yard art until pieced back enough to enable rolling it. That could be a problem from many angles. As it sits now, seeing that the inner pinion bearing is rolling around in the case there is no way to roll the truck on the rear wheels and at the prices you quoted shopping for a replacement truck does seem the best option.
I am curious as to what caused the pinion nut to back off.
You will need to tell US why it fell off… As the guys have collectively stated…It either fell off due to failed U-Joints, Loose bolts or a Broken Yoke at the rear axle or rear of tranny. It wouldnt be difficult to see why it fell off. You will either need to buy a new shaft due to damage…or replace one of the yokes, or the u joints… The U-Joints are the MOST COMMON cause of this type of issue…and are the easiest to remedy. You should NOT need a hydraulic press to install the U-Joints…
Blackbird
Just curious. If I could get a rear end super cheap, how would I know if it’s compatible? Suppose I could get one of a '99 instead of a '97, but it’s the same truck and the same gear ratio. What if it’s 2WD instead of 4WD? What if it has a different cab style?
I believe a 1500 rear axle assembly from 1994 to 2001 will bolt in. Ask your salvage yard, they have an interchange catalog. Many 4WD’s came with a locking rear differential, you can live without that feature. 95% of the 1/2 tons came with 3.55 axle ratio, should be easy to find.
The biggest challenge for the novice will be dealing with the rusty U-bolts, brake cables and brake line. Not a big deal for a mechanic, should take less than 4 hours.
How much does an axle weigh? I was really surprised at how light the drive shaft was. But the whole rear end? Can I move that around by myself?
Rusty bolts don’t scare me. Everything looks extremely easy to access, even if I have to get a cheater bar or a grinder in there.
Brake cables are optional. =D I don’t think my parking brake really even works now. If I could get that working, it’s a bonus.
I did shocks on my old Suzuki Sidekick. That wasn’t hard.
The service brake lines are going to be the challenge for me. I’ve done a handful of brake pads and shoes. I never actually disconnected a brake line. One mechanic cautioned me that those are likely in rough shape. I have no clue how to replace a brake line.
A couple of mechanics have quoted me $600 to $700. So they are basically thinking it’ll be a full day job. For a novice without a garage or a lift or half of the right tools in the middle of January? Maybe a little longer.
Not an all day job for a shop. They have to allow room in the estimate for expected replacement parts to go with the job. New U-bolts, brake hose, wheel cylinders, brake shoes, brake fluid and gear oil. They don’t know the condition of the brake parts on your rear end or the replacement rear until they see them in the shop.
A person could replace that rear end in the driveway in 4 hours if the additional parts are close by. For some just disconnecting and reconnecting the brake hose and bleeding the brakes it is an all day job. For an experienced technician it takes 20 minutes.
I think that rear end weighs about 175-200 Lbs. Save this for a spring project, drive something else in the meantime.
If the alternative is the junk yard, no harm in taking it off to see what’s involved. Heck, before I scrap it, I should take the whole engine apart.
I’d be inclined to pay a shop to swap out the rear end, before giving up on the truck just yet
Don’t take this the wrong way, but it sounds like you’re not really set up to do this job yourself
Someone familiar with the various incidentals of changing a rear axle could easily do the switch in less than 4 hours @Nevada. If they have a suitable place to work and all the various pieces of equipment and tools. In a well equipped shop the job could be done in less than 2 hours.
And as for the gear ratio. How many ratios were available? Installing a 3.70:1 in place of a 3.55:1 would hardly be noticed by most drivers and would result in the speedometer registering 53 when the actual speed was 50. That wouldn’t be a show stopper for me.
I’m not sure about a Chevy, but I did a rear axle swap out of a Nissan SUV many years ago in a driveway with hand tools and jack stands. That took 6 hours, but only because we dropped out the rear axle and took it with us to the salvage yard to match up with the replacement before dropping the cash. Round trip drive took us about 2 hours. And that was waiting for them to drop the axle out of the wreck. We took about an hour and a half, they took 15 mins! But, we used wrenches and pliers, they used torches and cutters.