1982 Huntsman U-Joint?

[HUntsman]

I thought it was front end but realize the knocking sound I am hearing

is coming from deepunder just between the 2 front seats.

Is the driveline joint the possible culprit?

There is a connecting joint just where the 2 drive lines meet there.

A deep knocking comes and goes but clearly in sync with wheel revolution.

Not wheel bearings.tires good/balanced.

ANy suggestions?

Thanks

Edited January 6, 2013 by HUntsman

[90toydolphin]

crawl under and see if there is any play at the joint. been years but have changed them, not that hard if you like turning a wrench. if not inclined i'd take it to a general repair shop you trust. if it's vibrating hard enough to cause a knock it might damage trans or rearend if not fixed.

[WME]

There are 3 u joints on the drive shaft. Also the automatics have a rear output bushing that has been known to cause problems.

SAFELY jack up the camper and get under and check for lose things.

[stamar]

oh man i did this job on my bmw and it was hell incarnate. Im sure its easier on a toyota.

[Skydancer2992]

I just replaced one of my U joints in September on my 91 Warrior. At first I thought it was a tire harmonic from new front tires because it only seemed to occur at around 30 mph.

While crawling under the camper to replace my fuel filter, I pushed on the drive shaft and it shifted about a half inch. I rotated it about 30 degrees back and forth and it shouldn't do that. That should not happen. It should be firm in place with no play whatsoever.

Examining the U joint, I could see that one of the bearing cups was about half worn through and was not far from allowing the shaft inside to break through. My planned trip in five days to the Ron Coleman Quartz Mine was in danger unless I acted fast.

Working on my back, I removed the drive shaft which was surprisingly easy but uncomfortable. Four bolts connecting the drive shaft to the differential, two bolts on a support bracket and four bolts holding the two drive shafts together. The shaft slides out from the transmission so easily you will accidentally let it fall and clatter on the concrete.

Recommend a Sharpie pen for making alignment marks so that you can confidently put everything back into place like the original orientation.

Picture of the universal HERE.

Getting the old U joint out became a challenge. Even with a hydraulic press at a the Navy base auto hobby shop, it wouldn't yield and was starting to damage the drive shaft. The part did have 230,000 miles on it and was disfigured by damage. The guy on duty at the shop ended up cutting one of the cups off to free the spyder so that it could be pulled out.

The press was a big help although the new spider was a bit stubborn going in.

Reinstallation was easy enough but since I had not used a sharpie to make marks on the shaft, I assembled it 180 degrees off original orientation, thought better of it, and reassembled it correctly. May or may not have made a difference. I had made scratch marks with a screwdriver but in all the work on the shaft, the marks were hard to find again.

I learned a lot. However, it may have been easier to drop the drive shaft off at a machine shop with the new spyder joint and paid them to replace the joint. I wasted about six hours trying various ways to remove the old spyder.

[zero]

I thought it was front end but realize the knocking sound I am hearing

is coming from deepunder just between the 2 front seats.

Is the driveline joint the possible culprit?

There is a connecting joint just where the 2 drive lines meet there.

A deep knocking comes and goes but clearly in sync with wheel revolution.

Not wheel bearings.tires good/balanced.

ANy suggestions?

Thanks

Better check the driveshaft support bearing. Unllke the u-joints, it is turning anytime the truck is moving. The Toyota driveshaft is fairly straight so the u-joints move very little. They can go bad in ways. They can get "frozen" which causes vibration the faster you got. Or they can dry out and get loose. Then is will "clack" or "thunk" when you first take of. I'd yank the driveshaft off and check the u-joints and support bearing. It's the only sure way to check it properly.. Toyota u-joints are small and relatively easy to replace. A c-press or a big bench vise works fine. You usually cannot just press them out though. It takes some finesse and coaxing. You press on one side of the yoke and shock the other side with a hammer and a large drift pin. If you don't, simple pressing can distort the yoke.

[HUntsman]

Thanks everyone for the inputs.

[stamar]

the csb part normally goes out when the u joint is bad. it just prevents a little wobble it wont be the culprit whne its banging. but its part of the whole job. Id do a complete walkthrough on this job and have the right tools handy theres a few ones you probably dont have handy

the true purpose of the csb is just to prevent the driveshaft from falling on the ground when you stop. but it has the rubber part to help with a small wobble. when its a big wobble it will tear.

[5Toyota]

i dont need to remind you what happens if the joint breaks and the drive line comes up thru the floor saw a pickup with a driveline threw the bed floor once try too replace with greasable joints should be able to had to do this on my 4wd

[zero]

i dont need to remind you what happens if the joint breaks and the drive line comes up thru the floor saw a pickup with a driveline threw the bed floor once try too replace with greasable joints should be able to had to do this on my 4wd

I had my rear driveshaft fall off on my 1986 Chevy Blazer-Chalet 4WD RV. The damage as a 75 MPH and was pretty severe. Rear shaft fell off, cocked, tore off both sides of the dual exhaust and parking brake cables - and the NP208 transfercase blew to pieces.

[zero]

the true purpose of the csb is just to prevent the driveshaft from falling on the ground when you stop. but it has the rubber part to help with a small wobble. when its a big wobble it will tear.

Not true. The driveshaft center support is there for two major reasons (and not to just hold off the ground). #1 it is there to allow a two piece driveshaft (in two different planes) instead of a single driveshaft. It supports the middle section that is articulated. #2 - in the Toyota, it allows for "for and aft" movement of the driveshaft into and out of the transmission. When ever the rear suspension goes up or down, the driveshaft moves into or out of the transmission. Other makes of trucks use a second splined slip joint to do this (when they have two pieces shafts). Toyota does it with the rubber in the center support.

As to when they go bad? Has little to do with worn u-joints. It has a sealed ball bearing that turns ALL the time when the vehicle moves. It HAS to wear out after a certain amount of miles just like any non-lubed bearing. It ought to be checked every 50K miles for a vehicle with long trips in mind. That being said I've seen them last 150K miles before the bearing dries up and when it does it usually starts making noise as a warning. Same goes with u-joints. They are also non-lubed bearings (unless they have grease fittings). Needle bearings instead of ball bearing and the "sealed" joints with no grease fittings usually last longer then the ones with grease fittings. On vehicles like Toyotas with near straight driveshafts there is very little movement in the u-joints and they sometimes get stuck, i.e. "frozen" instead of getting loose. When stuck the driveshaft will vibrate and get worse the faster the truck goes.