H 4WD Grinding/Growling Issues (1 Viewer)

[RedRockTaylor]

Howdy Folks,

This weekend when driving on well packed dirt roads I decided to throw my 62 in H4WD as I just rebuilt the front end and still haven’t hit the miles on it to drain the fresh metal shavings out. Upon doing so I discovered that when I went over 20-25 MPH I would start to hear a low grinding/growl from the front end and near the passenger side. The noise was much worse when I unlocked my hubs. This noise is only present in H4WD, 2WD has zero issues. And L4WD has worked like a dream and not given me a single worrying sound. So this leads me to believe that it has to be one of three areas; the t case, front drive shaft, or the axle. Unfortunately for reasons you will soon understand I have no idea if this noise was present before the front end rebuild, as I couldn't use 4WD on it.

For the Axle, considering my old man(he’s been working on cruiser since I was born in 99) and I just rebuilt the entire front end, including a new set of gears from cruise outfitters, arb locker, knuckle rebuild, and rotors. I want to say that it is very very unlikely to be anything inside the axle. That leaves me with the drive shaft and T case. Today I took a look at the drive shaft and there was basically no play at either of the U Joints so I then took the drive shaft out and drove the 62 around hitting 25-30mph with H4WD engaged and the noise has disappeared. But I’m not sure this really eliminates the t case as the source as there is no weight being put on it with the drive shaft out, so sure the flange is still spinning but not sure it means much. When I was under there I also spun around the T Case Flange on the front and it was making a bit of a grinding noise, seen here. Does this sound like a bad output bearing? Mind you the T case shifter was in neutral when I was spinning it in the video.

Also it should be noted that I drained the T Case oil trying to diagnose this issue and I didn’t find/feel any metal shavings in it at all. Buuuuut only about a cup of oil came out of the thing and it was very brown. (Forgive me for not baselining this Cruiser properly when buying it, it’s my first Cruiser/old vehicle.) I filled it back up to the fill plug with 80-90 and it still made the grinding noise.

A bit more of important background on this 62.

The PO had installed 4.88 gears on only the rear(the main reason we started the front end rebuild was to put the correct gears in.) so it’s very possible he drove it around in 4WD with the mismatch and blew the T case himself. As I only used 4WD before the front end rebuild for maybe a total of half a mile and at a very slow speed>5MPH.

It has at least a 2” OME lift with reverse shackles (the splines of the front drive shaft had more than safe enough room for this) additionally there are already shims installed on the axle to account for the lift and provide a better angle of attack for the drive shaft.

I have done a lot of research on my issue and have come across a few good threads that I put to use diagnosing the problem, but I need your guys help getting me across the finish line.

Thanks,

Taylor

 

[HawkDriver]

Well written write up Taylor! As we’ve nearly concluded in our diagnosis together, you are zeroing in on the problem. I’ll let others chime in here too, being that’s what you are asking for.

We should mention two other signs of PO abuse/neglect. The T Case fill plug is completely stripped so this janky “boat plug” type of arrangement is what we discovered yesterday. As well as just the minimal amount of what smelled to be ATF that we drained from the T Case and no sign of 90W gear oil…

And second that the T Case front flange stake nut has clearly been on and off up to at least 4 different times. Leading one to believe that some investigation and suspicions had arisen to the PO sometime prior.

My guess is…. well, let’s just see where this discussion goes. Sorry for your woes bud. Hang in there! She’s a good Cruiser!

 

[OSS]

These symptoms are identical to the ones on the thread linked below. There’s also other threads on mud complaining about the same thing.

Grinding Noise from front end!!! Please Help

So here is what's happening. I was about order sliders to get welded on on the 20th. I got into my FJ60 that had been sitting for 3 wks (out of town and no time to play with her). I had locked the from bus and put her in 4H to get out of the snowbank that surround her. She got out easily and I...

forum.ih8mud.com

 

[RedRockTaylor]

These symptoms are identical to the ones on the thread linked below. There’s also other threads on mud complaining about the same thing.

Grinding Noise from front end!!! Please Help

So here is what's happening. I was about order sliders to get welded on on the 20th. I got into my FJ60 that had been sitting for 3 wks (out of town and no time to play with her). I had locked the from bus and put her in 4H to get out of the snowbank that surround her. She got out easily and I...

forum.ih8mud.com

Yes, those are the afore metioned research threads I used to help diagnose the issue on my rig. Unfortunately, none of those threads really came up with a solid answer that applies to my rig, and I truly cannot believe that this is a standard noise to be heard when driving H4WD fast on a high traction surface. I hope I am wrong about that and it is normal, but I have never heard this noise in the 80 or 100 when using H4WD at speed.

I am hoping that the T Case Flange rotation sound I linked is something someone can help identify if it's bad noise.

 

[OSS]

I have never heard this noise in the 80 or 100 when using H4WD at speed.

The 80 series and onward implemented Full Time 4WD to address this very problem. Those vehicles can go 100 mph in 4WD on pavement no problem. As you probably know, those vehicles have a differential gear assembly in the transfer case that prevents driveline binding.