Tested my 4wd today.. Problems..

[Shawn5800]

Hey there guys. After testing my 4wd today to get it ready for winter i realized that there is something wrong.

The truck will engage in both 4 HI and LOW perfect. No issues there. I can drive it and feel that both are working and engaged. But there is a loud slapping sound, and it increases in its speed as the truck goes faster. Its coming from the front drivers side. I thought maybe that rubber wheel well crap thats riveted up inside there got caught but its fine.

On all my old 4wds i could have sworn that the 4wd shaft was always spinning but just not engaged. Is it not the same on our 4RS? What changes are made once i put the truck into 4 wheel that wouldnt normally be spinning/turning in 2wd. The previous owner also ripped off part of the plastic protective pan underneath and i noticed he ziptied it as tight as he could to the bottom of the truck. Is that where friction could be happening?..

It never had this sound when i first bought the truck. Maybe when i brought it home and tidied up the bottom i moved one of the plastic pans to far over?

Help guys! Thanks!

 

[Baja Runner]

First thought would be lubing the front driveshaft. Or check to see if its rubbing against something.

 

[88xtraSR5]

Maybe your neighbors cat crawled in wrong spot?? I'd check the driveshaft, cv's, all the hardware and skid plates??

 

[brian2sun]

On all my old 4wds i could have sworn that the 4wd shaft was always spinning but just not engaged. Is it not the same on our 4RS? What changes are made once i put the truck into 4 wheel that wouldnt normally be spinning/turning in 2wd.

The front driveshaft doesn't spin on our trucks in 2wd. Nor do the ring and pinion. However, the CVs spin passively from the rear tires pushing and that spins just the carrier inside the front diff in 2wd. From your description, I doubt it's CVs because they spin regardless of 2wd/4wd. I would try greasing up the driveshaft like Baja suggested. I would also drain the front diff fluid and see if there are any metal chunks.

 

[theizzardking]

i'd check and change your diff and t-case fluids grease the rear drive shaft and hope that sorts it out.....and really you should do all of that anyways to be ready for the winter.

i'm no pro with the t-cases on these 4runners, but if they are chain driven there is a chance the chain has stretched in the t-case and is slapping around in there when it's engaged, I've ran across this problem before on a number of jeeps i've owned in the past, not sure how common it is on the 4runner or even if your case is chain driven in the first place.....i'll let some of the pro's jump in here and correct me if i'm wrong...but really it's the only thing i can think of that would create a slapping sound in 4wd but not 2wd.....
good luck man!

 

[theizzardking]

The front driveshaft doesn't spin on our trucks in 2wd. Nor do the ring and pinion. However, the CVs spin passively from the rear tires pushing and that spins just the carrier inside the front diff in 2wd. From your description, I doubt it's CVs because they spin regardless of 2wd/4wd. I would try greasing up the driveshaft like Baja suggested. I would also drain the front diff fluid and see if there are any metal chunks.

oh ha! i think i misunderstood him on what was spinning in the front....


brian is right ^

 

[Shawn5800]

Update! After taking her off road today i realized that the truck will not make the sound when driving in a straight line. It only makes the sound when i cut the wheel left. It gets louder the harder i turn. The right turns i never hear it. And it still sounds for sure like its RIGHT underneath my foot. I cant figure this damn thing out! Wheel bearing?

Its almost a grinding sound now. It seems to be loosening up a bit now to and its not as loud. Any more ideas?

Thanks for the help guys!

 

[Gerdo]

Sounds like a bad left CV.
A bad CV will make noise when under power when turning in that direction.