89 MT 4x4 Grinding on coast or decel

[WizBang]

My 89 Tracker 2Dr 8V (175K miles with orig. MT and TC) has a nasty grind when I let off throttle.

Repairs/mods of note:
-> new Clutch 2018 incl. good Japanese throwout and pilot bearings.  Maybe 2000km on it since (hunting vehicle)
-> new fluids in tranny (GL-4), diff's and transfer case (GL-5) at that time
-> 3" suspension lift with appropriate 1/2" driveline spacer @ rear diff, running 30x9.5 BFG KO2's
-> new universals throughout
-> this vehicle spends 75% of it's driving time in 4x4, likely 50% of that in 4Lo (except when being towed.  When towed, I stop about every 100km to run the vehicle through the gears with the TC in neutral to splash the top bearing)
-> lots of front end weight with bush guard/winch box/winch and also a SnowSport Plow up front when using to push snow (this is an amazing plow set-up, btw)

The symptoms:
-> metallic grind when I let off throttle.  Not clicking or whining.  Grinding!
-> occurs in 2WD and 4WD, and whether hubs are locked or not
-> worst in 5th, much less in 4th (main shaft needle bearings??)
-> disappears when clutch is disengaged (pedal pushed). Hmmm, can't recall if it still grinds coasting in N.  My recollection is that it doesn't.
-> front diff pinion bearing could be starved of lubrication because the lift kit necessitated topping up higher than the fill hole (I inclined the vehicle and filled it as best I could but it wasn't inclined as high as the lift kit supplier recommended)

The diagnosis:    


Feel free to weigh in...

[fixkick]

My 89 Tracker 2Dr 8V (175K miles with orig. MT and TC) has a nasty grind when I let off throttle.

Repairs/mods of note:
-> new Clutch 2018 incl. good Japanese throwout and pilot bearings.  Maybe 2000km on it since (hunting vehicle)
-> new fluids in tranny (GL-4), diff's and transfer case (GL-5) at that time
-> 3" suspension lift with appropriate 1/2" driveline spacer @ rear diff, running 30x9.5 BFG KO2's
-> new universals throughout
-> this vehicle spends 75% of it's driving time in 4x4, likely 50% of that in 4Lo (except when being towed.  When towed, I stop about every 100km to run the vehicle through the gears with the TC in neutral to splash the top bearing)
-> lots of front end weight with bush guard/winch box/winch and also a SnowSport Plow up front when using to push snow (this is an amazing plow set-up, btw)

The symptoms:
-> metallic grind when I let off throttle.  Not clicking or whining.  Grinding!
-> occurs in 2WD and 4WD, and whether hubs are locked or not
-> worst in 5th, much less in 4th (main shaft needle bearings??)
-> disappears when clutch is disengaged (pedal pushed). Hmmm, can't recall if it still grinds coasting in N.  My recollection is that it doesn't.
-> front diff pinion bearing could be starved of lubrication because the lift kit necessitated topping up higher than the fill hole (I inclined the vehicle and filled it as best I could but it wasn't inclined as high as the lift kit supplier recommended)

The diagnosis:    


Feel free to weigh in...

4th gear is not gear,at all, (key fact) and it just locks up the to main shaft 1:1 ratio.  no load on the cluster below. (neat to know ,trouble shooting)
same thing in the transfer case end to end lock up in  2wd, no load on the chain for it to make noise.

one odd thing on front end locking hubs,  manual or automatic,  the hubs inside rust and you  think the knob set to unlocked is not  working and is 1/2 engaged and makes huge noise.
same with autohubs, you do not have, 1/2 engaged noise.
the test is simple drove the hubs totall,  4 bolt. and drive. (no rain day to keep water from landing there)

front diff bearing does not move ever 2wd, if the hub locks are not bad so, those are first.

remove all screws #6  and the cap it holds totally as  test, and  now the CV shaft go dead, as does the the whole front axle.  (this hubs love to fail and even make huge racket)
and in 2wd mode. so ransfer case does not spin the front axle front pinion at all. and is now dead, not spinning;
GOAL fix 2wd first. 4wd last.  ( I hope parts below are not 14-9 are not GM  tracker parts) below is pure suzuki from Iwata japan or CAMI canada plant.

[fixkick]

parts on cars this old have a bad habit of mix up.
do not have this thing, (GM uses this beast to hold the wheel bearings under 150ft/lbs torque. and strange tool.

[fixkick]

is this you?> ???

http://www.fixkick.com/videos/AVI/kickin.mp4

[WizBang]

is this  you?>  ???

http://www.fixkick.com/videos/AVI/kickin.mp4

Haha, no!  But we have about the same amount of snow right now (Vancouver, BC, Canada)

I will have to wait until better weather to disconnect the hubs.  Lots of snow and road salt.  I think the hubs are functioning okay though.  They were completely overhauled (cleaned and re-greased with marine grease) a few years ago.  They turn LOCK-UNLOCK easily, and it readily engages and disengages the front wheels (evidenced by its driving behavior, not just by the "4WD" light going on)

[fixkick]

is this  you?>  ???

http://www.fixkick.com/videos/AVI/kickin.mp4

Haha, no!  But we have about the same amount of snow right now (Vancouver, BC, Canada)

I will have to wait until better weather to disconnect the hubs.  Lots of snow and road salt.  I think the hubs are functioning okay though.  They were completely overhauled (cleaned and re-greased with marine grease) a few years ago.  They turn LOCK-UNLOCK easily, and it readily engages and disengages the front wheels (evidenced by its driving behavior, not just by the "4WD" light going on)

great
ok cleaned and greased. manuals.
so that means the CV  and front axle are dead in 2wd, if the transfer case lever not messed up
it is 2wd drive only problem with 1/2 the parts dead (not turning)

I have remote electronic stethoscope to find this.  easy. mics clamps to earphones, that finds any noise . (mostly)
maker steelman.

https://fixkick.com/NOISE.html


clamp to anything thing not spinning and drive.
vast places to check.
even brakes can make hellish noises, even not braking,. missing shims etc. sticking calipers, or there slider pins jammed, or wheel cylinders sticking etc.
4th gear should be quite, 2 bearing front and read ok.

nothing beats the stethoscope for sure 2 persons, one drives only and other orders stop and move mike clamps.
an amazing tool.

find what corner of car makes noise, or down the center line 3 places. bingo found it. ( no gear box s dead silent for sure on a MIC) purrs yes.

or this,
a goCAM duct taped to see front CV spins in 2wd,:?? now that tells you fact #1, must not .

[WizBang]

Okay, great suggestion. I've ordered the Steelman 06600 ChassisEAR unit. Plugged my nose and bought it from Bezos due to limited options here in Canada.

Confident I can hone in on the source with that. Will update...

[fixkick]

Okay, great suggestion.  I've ordered the Steelman 06600 ChassisEAR unit.  Plugged my nose and bought it from Bezos due to limited options here in Canada.

Confident I can hone in on the source with that.  Will update...

hope it saves lots of labor time,  and allows work no risks. (remote is safe)

are those new U-joints rear,  forged? or raw cast iron from china?(no name ) also on installation it is so very easy for a needle  to fall out or get bent during the press install.

forgot to say this before
as it makes NOISE max does lightly applying main foot brake stop or change the noise?
and in the same vein,  does lightly pulling up hand brake lever, &  hold the button down so it can not latch up (ratchet) and does it change noise?
good luck to you finding this  noise.

[WizBang]

I can do some of the brake testing while waiting for the Steelman unit to arrive.

Important update!  I determined today that it is not grinding in 2WD.  That narrows the search considerably.

[fixkick]

hah haaaaaaaaaaaaaaaaaaaa
that is is a good discovery. huge in fact.
front CVs are next, those fail first in most cases, for sure gear boxes always full of lube
front end noise,. I bet and the microphone tool will prove that. clipped to axle casing front or to transfer case.
good luck to you !