Rear drivetrain "Kink" sound

[Gerdo]

I have had this sound for a year or two now. If the vehicle is stopped and I let out the clutch a little aggressively I get this "Kink" sound, only once. If I stop and go again it usually doesn't make a noise. If I do the same thing in reverse it will also make the sound. If I do a forward/reverse/forward it'll do it every time. If I'm backing up an incline it'll kinda sound like the rollercoaster going up the hill. (kink kink kink)

I have pulled the rear driveshaft and driven around in 4Hi and it is perfectly quiet. I also rotated and felt the u-joints and everything felt tight and smooth. I have always kept them well lubed, the slip joint too.

Could this be the clunk that LC 80s have? (driveshaft)

Any thoughts.

 

[Singtoe]

If it is not the U-joints, (which you said you checked), it sounds like the bushings in your 4 link set up my be going out.

To check for this, set the parking break so the truck won't move and have an assistant try to drive the truck. you should see the rear axle defect and you might even see where it is making the noise.

Safety is first. Try to do this test with rear tires off the ground, so that if the parking break doesn't hold, it won't run over anybody accidentally.

Edit: I did not pay attention to the reverse part. If it is making the klunck, klunck noise - it probably is the driveshaft -slip joint. You can still lift the truck up in the air, rest the rear axle on jack stands that way your drive shaft is in its current position and try to listen and see where the noise is coming from.

 

[cj80cruiser]

I have had this sound for a year or two now. If the vehicle is stopped and I let out the clutch a little aggressively I get this "Kink" sound, only once. If I stop and go again it usually doesn't make a noise. If I do the same thing in reverse it will also make the sound. If I do a forward/reverse/forward it'll do it every time. If I'm backing up an incline it'll kinda sound like the rollercoaster going up the hill. (kink kink kink)

I have pulled the rear driveshaft and driven around in 4Hi and it is perfectly quiet. I also rotated and felt the u-joints and everything felt tight and smooth. I have always kept them well lubed, the slip joint too.

Could this be the clunk that LC 80s have? (driveshaft)

Any thoughts.

The LC 80s clunk/thud was typically fixed with lubricating the slip joint. Some described the need to remove the driveshaft, pull the shaft apart, clean with brake cleaner or the like, and hand grease everything upon reassembly.

One thing I was warned about when greasing the slip joint was not to over fill as it would/could/maybe/might damage the t-case....that was never proven, just speculated.

Read post #2...they are in the 100 series section but it was an 80 issue too....could possibly be a 4runner issue????
Mobil 1 synthetic grease nlgi no 2

 

[Gerdo]

I have heard about the LC80/100 thunk.

Mine is a faint kink sound and it can't be felt.
Tomorrow I'm going to pull my rear DS and feel the U-joints again. I'm also going to pull the slip joint apart, clean and regrease.

 

[Gerdo]

I pulled the driveshaft this morning. Purged all the grease out of the slip jiont. Everything is tight and quiet. There is a slight hitch in the rear u-joint when moving it slowly. It's at the driveshaft shop for them to look at it.

 

[Baja Runner]

I'd bet $5 (maybe $10) that its the panhard bar. Or yes, it could be one of the other link bushings.

Do you have an adjustable one from SS?

 

[Gerdo]

I'd bet $5 (maybe $10) that its the panhard bar. Or yes, it could be one of the other link bushings.

Do you have an adjustable one from SS?

I haven't ruled out links yet.
I'm running my stock PHB with a welded on braced PHB drop.
I did pull the DS, cleaned and lubed the slip joint. I did find a u-joint with a hitch in it so I had it replaced and the DS rebalanced. It is smoother now but it did nothing to the sound.

 

[Gerdo]

Still have it.

 

[J-money$$$]

TIghten the heck out of you panhard bolts. Maybe link bushings. My truck makes so many pops and bangs idk what is what any more. But at one point i had my panhard bolts come slightly loose and made a clunk.

 

[Gerdo]

I just re-torqued everything with no joy.

 

[J-money$$$]

problem with the backlash in the diff?

 

[steezemcqueen]

Mine does it too. I only notice it when i am in 4lo and i am flexing. I always thought it was the driveline loading and unloading but now i'm not so sure. I think i might have worn link bushings. In the near future, i am going to be installing some new lower links. We'll see if that helps.