loud clicking (grinding) noise in 4lo

[run4yota]

i have a odd problem, searched everywhere and cant find any answers...

1995 4runner sr5 3.0 v6 auto 4x4 :

when i put it in 4hi no noise, 4lo going strait and light throttle no noise

4lo around corner clicking almost like an internal grinding from inside the transmission area. if i'm going straight and get on the throttle in 4lo it makes the same sound. the noise is in-sync with the speed of the truck. i know it's not the cv's, they are new and at full droop i'm not binding at all. it's most noticeable when i'm in soft sand, or chugin up a hill. my best guess is that the transfer case chain is loose and needs adjusting (if possible) ?

anybody have the same or similar issue? -thanks, Nick

 

[fourwd1]

The chain is used to drive the front output in both 4Hi and 4Lo range.
There's no adjustment and they really don't fail too often. The fact that it only happens when turning kinda points to something in the front end.

 

[Bad_Vision]

bearings my friend bearings.
when your on the pavement the pressure keeps the bearing seated solid but when your in sand it can move or slide around the bearing is free to click and hop and all other stuff, its not bad per say, but i will cause it to wear down faster.
Click it until your broke on the side of the road or just replace the cheap labor intensive parts.

And just FYI just because a CV shaft is new does not mean it was rebuilt in the last few weeks some shafts sit on a shelf in a warehouse for 10 years without moving and all the grease will settle on one side and when you start driving it its bare metal for a little while.

 

[run4yota]

ok thanks, which bearings do you think it would most likely be? any way to diagnose the problem better?

oh i also noticed that it does it on and off pavement.

 

[Bad_Vision]

hmmm, i know with a hub assembly you would just turn left and right in a slalom style to determine witch bearing was bad.
ok this will help you determine whats wrong all you need to do is have two people one to drive and one to listen to the front end.
ok you'll need a parking lot simply have the driver turn hard left and go in a circle the other person will stand outside by the left tire as the driver slowly moves forward look to see what is clicking, you will get a idea of what is clicking. do the same thing for the right side.
Please post what you find and i can get a better idea of what is wrong.

 

[run4yota]

it does it when going straight or slight turn in deep loose sand, and going up steep hills. on pavement it does it turning both left and right but more so when i'm going left. i also noticed that everytime it clicks or grinds the transfere case shifter shutters at the same rate and if i push the shifter up so it's between 4hi and 4lo it reduces the severety and or stops the clicking all together. it's an ADD system.. not manual hubs (not sure if that makes a difference) thanks again

 

[Bad_Vision]

might be the front drive shaft joint?

 

[run4yota]

i would think that, but it started almost instantly, never made a sound, then i'm offroading one day down a dried river bed and it starts clicking out of the blue.. and that still doesnt explain that it's in 4lo only :/ hmmm this one is a real head scratcher

 

[Bad_Vision]

at higher speeds the u joints cap could be the sound it would make sense that in 4 hi it would have enough centrifugal force to not make the noise?