Clunk from front diff or transfer case?????? :(

[KZJ95Beast]

Have a kzj95 prado. Japanese model with the 1kzte intercooler and cable type throttle.

Having an issue where there is a clack clack clack when full throttling it from a standstill. Put it in HL or LL and it does it constantly no matter what. Like something hitting something hard.

Just removed the front diff driveshaft and it won't move on H. However on HL and LL it moves. LL would take off aggressively and slow down I assume this is to get out of heavy mud or so.

HL moves normal. However when I full throttle it from standstill, it moves without the loud clack noise.

Questions......is the prado operating on front wheel drive on H or is is bcuz of no resistance on transfer case to front diff causing the rear not to engage?

Also could that noise be coming from the transfer case or the front diff? I'm trying to figure out if the no load on the transfer case is why no noise or is the front diff having an issue causing the load with the front shaft on to cause the transfer case to make that noise?

Really don't want to remove transfer case or get another one and it might be front diff or is it that the transfer case knocking up due to issues to spin the front diff?

Still on original rims and tyres. I've changed every suspension parts and bushings front and back and mounts to make sure.

Thanks on advanced.

 

[KZJ95Beast]

Also did new bushings for the front diff brackets both of them thinking it was that and it wasn't the issue.

 

[little_joe]

Having an issue where there is a clack clack clack when full throttling it from a standstill. Put it in HL or LL and it does it constantly no matter what. Like something hitting something hard.

Just removed the front diff driveshaft and it won't move on H. However on HL and LL it moves. LL would take off aggressively and slow down I assume this is to get out of heavy mud or so.

HL moves normal. However when I full throttle it from standstill, it moves without the loud clack noise.

Questions......is the prado operating on front wheel drive on H or is is bcuz of no resistance on transfer case to front diff causing the rear not to engage?

Your understanding of how the transfer case/center diff works is correct. Since there is no resistance to the front when in H, the center diff will send power there. When you lock the center, transfer case sends power both front and rear.

Another cheap troubleshooting action: drain the gear oil from the front diff, see if you get any chunks. It's impossible to tell from just words, but it almost sounds as if your front diff has given it up. After draining but prior to refilling, swirl a finger inside the diff case around the drain hole and see if there's anything there.

I'd also suggest lifting one side of the front end and spin the tire by hand, listen carefully. Then do the other side. Then get both front wheels off the ground and do it again.

If everything checks out during this process, time to move on to the transfer case. But make sure your cv's are good, nothing loose such as swaybar/endlinks, camber bolts/control arms, strut mounts, etc.

 

[KZJ95Beast]

Hey, drained the oil but was clean. Pulled the transfer case down and scrapped it to see the chain very slack. Just holding it up would touch the casing.

Got everything to replace and just got done reinstalling the transfer case. Will be testing it out later or tomorrow to see if it goes away.

 

[KZJ95Beast]

Back up running and no more noises