4x4 Rear diff seizes up

I'm new here and have looked for info on this issue but with no resolve. Hoping for a little help!
2009 Toy Taco Dbl Cab 4 x 4, 6" lift, 35" tires, has e locker.
Took the boat to the river, once the boat was launched I put the truck in drive and it seamed to be stuck, I rocked it a few times and it wouldn't go. I put it in neutral and then back to drive and gas it, one wheel started to spin a lot (locker not engaged) so I put it in 4hi and was able to get going up the ramp. Once I was on level ground I went back to 2WD and it seemed fine. When I went to retrieve the boat, I drove about 5 feet and it locked up again. I stopped, backed up and it freed up. I backed down the ramp, loaded the boat and put it in 4WD. It pulled out of the water fine. Got to level ground and stopped after putting back in 2WD. Started to pull away and it locked up skidding the rear tires, maybe only one tire I couldn't tell. I'd back up and it would release and allow me to drive about 10 feet and lock again. Multiple times of this and I was able to move it about 100 yards. I decided to pull the e locker ( that I found out wasn't working) and manually lock the diff and try that, same results. I unhooked the boat and then it drove fine with no issues. Had to get my other truck to retrieve the boat and drove the Taco home. I replaced the elocker and now it's working. I need to hook the boat up and try to do that again to see what's happening. I have confirmed it's not the brakes and the trans and transfer case seem to working normal, has new gear oil and is full, just the rear diff binding up. WTF! Any ideas out there?

 

6" lift may have u-joint issues and the pinion has a crush sleeve that is set on install and the angle may have crushed it more and allowed too much play between that and the ring gear.
A heavy load can cause more driveline deflection like when pulling the boat. Not sure how you lifted the Tacoma but weak rear springs cause lots of issues under load.
ECGS has the option to set that pinion with spacers so won't move vs the crush sleeve. Then there are the bearings in the diff carrier and outer wheel bearing any of which can be failing. You need to jack the center rear up and see where the bind/noise is. That or take it to a driveline shop for an estimate and get their opinion. A shop charges around $2k for a rebuild with a new gear set and install kit but outer bearings are additional. You could have broken a tooth on the pinion or ring gear and its now in the spider gears. When the e-locker is locked the spiders do not turn.

You can read about the rear diff on the ECGS site in tech info if so inclined and you determine problem is in the diff.

 

Thank you for the reply. Here's little more info: I have only had the truck a few months and not sure what all has been done. The drive line and u-joints are new. The rear has 3" blocks under the leaf springs and not sure if the springs were replaced for the lift. Not sure if it's even a 6" lift, the seller said it was. The boat and trailer only weight about 2800 lbs. and maybe has 250 lbs of tongue weight. The truck didn't drop much when the boat was hitched up. It also towed the boat about 10 miles with no issues until the unloading of the boat at the ramp. The truck diff was locking up even when the trailer was empty. I had just pulled the diff to put in a new gasket that was leaking, all the teeth looked good, nothing looked sloppy or worn. I'm not a diff expert so I really don't know if the ring and pinion were misaligned or worn. Didn't look that close at the time since it was working fine before towing the boat. So I have to rule out, brakes, driveline, and spider gears since it was seizing up with the locker engaged and not. Sounds like the ring and pinion may be the issue...

 

If it wasn’t having any issues before and the problem started right after you pulled the diff to replace that seal I’m gonna guess something didn’t go back together right and that’s causing it.

 

That's what I would assume as well, however I never towed the boat before and not much can go together wrong when you just pull the 3rd member out and put it back in. Nothing was disassemble in the diff, axles out, diff out, new gasket, diff back in and axles back in. If something went together wrong I would have known it as soon as I drove it out of the shop.

 

Not necessarily. Sometimes if things are off just a tiny little bit it can cause weird issues like this in certain situations. You are probably correct but if it was me I would start by taking it apart again and do a thorough inspection on everything. It’s really all you can do. I might load up the bed with a few hundred pounds then lift the tires off the ground from the axle housing. Then you can spin everything and see what you see.

 

Thanks for the feedback!

 

Didn't you spray paint your diff purple? Thats prolly why it blew up

 

Hey Muddog321 where is the "ECGS site"?

 

has nothing to do with the needle bearing (ECGS). Change fluid on diffs and t case. check all drainage separately and carefully for water. regardless, put a diff breather extension on the rear. If you launch boats with it (ie. diff goes under water), this is a must.

 

The fluid was just changed in the diff and this is a diff issue not T-case. I understand a breather mod would be a good idea. Regardless, the gears in the diff are temporarily seizing and then releasing. Not a fluid issue.

 

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