Broken gearing

I was recently in a crash and thought I fixed all the damage but I’ve noticed a weird scraping/grinding noise coming from the back. After investigation I found that I’m getting no power to my rear right wheel. Is this something that could be fixed by new diff gears or could it possibly be the axle shaft. Would you recommend looking for a new diff or a whole axle?

 

How did you determine that the right rear isn't receiving power?

An open diff sends power through the path of least resistance. If you tested with the wheels off the ground, then resistance on the right side (eg, a sticky brake) could cause all the power to go to the left.

On the ground, a broken axle shaft on the right side would likely mean the truck wouldn't move at all. The axle internals would spin but the power would all go to the broken side since it's not connected to anything and therefore gives no resistance.

 

off the ground when I spun the right wheel the drive shaft wouldn’t move at all expect for every now and then there was a sticky spot. On the left side the driveshaft spun the entire time I moved the wheel.

 

Makes sense. When you spin one wheel, either the drive shaft or the other wheel should spin. If nothing's spinning, then I think you're right about damaged internals.

It's pretty easy to pull the axle shaft and check that. If the axle shaft looks good, then process of elimination says the diff is likely bad. You could also drain the oil and look for glitter.

To your original question of replacing the diff or the axle: I think either is a viable path. I've done all the work involved in both at home--I've replaced leaf springs, which is mostly the same work as replacing an axle, and I've replaced my 3rd member with the axle in place. In my opinion, replacing the whole axle is slightly more straightforward, since you won't have to deal with gaskets. If you're going to have a shop do the work, ask how labor rates compare for the two and do whichever is cheapest.

If you get a replacement 3rd member, you just need to make sure it's the right ratio and the right type (8"/locker or 8.4"/non-locker). If you get a whole axle, you also need to pay attention to ABS/non-ABS (you can use an ABS axle in a non-ABS truck, but not the other way around), and e-brake routing (most trucks route the brake over the leaf springs, but some later trucks route it under).

Now's a great time to consider regearing or adding a locker if those are of any interest to you.

 

If you had a broken drive axle in the back the truck wouldn't move in gear and it would roll when in park

Watch a YT video on how differentials work

That's not your noise, keep looking

 

That is how an open differential works.
Keep looking.

And who ever said pulling the axle was “easy”. Well, it is……
But but the brake line and brake cables have to come off. And if you have an E-locker, it’s a bit more involved.

Still, I think your issue is not with a broken axle. Bent maybe.
Broken? Not likely.

 

This....

 

Lift the rear of the truck, get it on body stands...
start it & put it in gear....
Using an automotive stethoscope, start isolating the noise till you hear the loudest point...
Use all your senses, eyes, ears, etc...

you may need to have someone work the throttle to find the sweet spot to isolate the noise correctly.

 

$26 Lisle 52750 Stethoscope Kit

https://www.amazon.com/Lisle-52750-...&hvlocphy=&hvtargid=pla-4583795269554955&th=1

you want the $25 one, & you want to use both attachments...
Sometimes you may hear something that you think is the issue using the rod attachment, & may be just normal noise...

 

Hey, Differential mechanic here. Sounds Like it could be an axle or the carrier that's broken. In terms of working on a rear diff, Toyotas are pretty straightforward. The only thing would be pinching the brake line as it comes down from the frame. I would start with a stethoscope and see where exactly it's coming from. I'm also curious on the accident and the damage you had, because your problems may not end once you eliminate the noise. You may also have a bent housing.

 

I went sideways into a guardrail. Wasn’t a super big impact but it best the steering rack and crunched the bed. It seems as if the damage is on the right side since that’s where I hear the noise and also seems like it’s catching with rotation. It’s a little weird cause it’s the opposite side of the impact but that’s how it was with the steering rack was too. The impact was on the drivers side but the drivers side of the steering rack was fine. I’ll have to do some more investigation but it sounds likely it’s a bent axle shaft, that would make most sense with the nature of the crash and the symptoms. Thanks to everyone trying to troubleshoot with me.