Whiskey Night (Driveshaft Flailing)

[lifeofduty]

Driving down the freeway. In a really bad place to break down, unmistakable clunk clunk clunk of driveshaft gone. This was @ about 10mph. Then no ability to drive forward as I roll backwards. Winching it on the tow truck, one wheel turned towards the front, and the other squealed backwards. (It was in park because in Neutral it was locked up) The driveshaft is disconnected from the rear diff. I had to hold up traffic on the on ramp for 45 minutes {still not dead yet}rck:
I expected it to be a U-joint gone bad. It wasn't. The nut that holds on the driveshaft (pinion nut?) to the splined and threaded differential shaft had let go. {Before the U-Joint, after the differential}. Is this heard of? I have never had this nut off. The last work done was by a shop replacing a transmission pack. Do I blame them? Regardless I need help on what to do. My gut says new driveshaft although it appears fine besides the u-joint clamp. Or is it cheaper to balance the driveshaft? If I had no outside help I would put a **** ton of locktight on it and torque to spec.
I should have seen this coming because today I heard a Whirring or Purring noise from the rear end while de-cellerating. Almost sounded like when your in high gear going down a hill with flowmasters. I got underneath and discovered the rear diff was 1qt low on fluid. I drove slow headed home after refilling and Wa-la. SHTF
Is this going to be expensive?
Is now the time to do 4.10 gears?
Any other suggestions, besides everyone who tells me to buy a toyota?
HELP!!!
Thanks.

 

[lifeofduty]

BTW the whiskey is great

 

[lifeofduty]

Any tech savy persons around ?

 

[MegaMouseGW]

I would have the drive shaft checked by a shop that specializes in them. Also have someone check out the pinion gear (best to have the whole dif checked). Your drive shaft may be alright, but not so sure on the pinion gear and dif. Depending on if the shop you took it to have the tranny work done took the shaft off using the nut (which they should not have), you may be able to get them to warrantee the work. Normally when transmission work is done and the driveshaft needs removed, most shops just take the shaft off the front universal joint.

 

[WhiteExpress]

Calm down and use the Enter key moar!

There is no reason why transmission work would involve removing the pinion nut.
It very much sounds like your spider gears took a dump on you and things are ***** inside your diff. The 'weak point' was the pinion.

I'd almost bet you need new gears / bearings at a minimum.
I can't see from your details, but if you're only a 2wd this a great chance to upgrade to some more aggressive gears (4.56s etc) for a minimal increase in price. If you're 4wd, it'll cost you a LOT more (front diff would have to be regeared too).

Drop that rear diff cover.

 

[lifeofduty]

I appreciate the advice. Shop says the same things mostly, waiting anxiously for a quote to see if its the opportune time to do 4.10 or 4.23 gears! Or maybe it's time for a trade in.

 

[MegaMouseGW]

I appreciate the advice. Shop says the same things mostly, waiting anxiously for a quote to see if its the opportune time to do 4.10 or 4.23 gears! Or maybe it's time for a trade in.

DO not trade in. It will cost a lot less to fix your truck than to trade it in. Plus why trade in a truck that has only one problem??

 

[chedched]

Toyota...haha!

I work there, don't do it.

Toyota doesn't rate their trucks for snow plowing. You can go ahead and pull a space shuttle (still chuckling about that one) but can't handle a plow...

Fix your truck. Worst case is a diff rebuild. I would have the shaft checked seeing you were traveling down the highway when it let go.

 

[Redtruck-VA]

Welcome to the forum. What you have described if I understand you correctly is that he pinion nut came off. This is actually a common problem. The "factory" let some of the newer trucks out without loktite and the same problem can be seen if a shop, usually when replacing a pinion seal and again re-uses the pinion nut without using loktite. The manual says to use a new nut, but I have re-used the old nut using loktite and have not had any issues. My guess is you simple had the nut come loose and now have collateral damage that needs to be identified. If you have gear damage then IMO this would be the time to do gear/differential. Good luck...