Clunk noise when changing between D and R

[Elfego]

Not sure if this is a concern. I’ve had this clunk noise for quite some time now.
Happens even when I come to a complete stop, wait 2-3 seconds, and then change gear.
T Case?

I’m sitting at 180k miles. Don’t think t case or transmission has had an oil flush.

 

[Desert Dino]

Check your drive shaft

 

[Desert Dino]

I’m sitting at 180k miles. Don’t think t case or transmission has had an oil flush.

Like never and forever? OMG

 

[Elfego]

Like never and forever?

From the time I’ve had it, no.
I bought it at 120k 10 ish years ago. I don’t know if the guy before me did. I have been flushing out old oils these past few weeks and definitely have considered transmission and t case.

 

[Desert Dino]

Do not flash the trans!!! just drain it and add good quality oil Dexron III drive and change again until looks ok

10years?? i do it every year all fluids and after 6 months engine oil + filter only every 2 years brake fluid + steering oil

 

[Desert Dino]

SEE FSM

 

[BILT4ME]

Not sure if this is a concern. I’ve had this clunk noise for quite some time now.
Happens even when I come to a complete stop, wait 2-3 seconds, and then change gear.
T Case?

I’m sitting at 180k miles. Don’t think t case or transmission has had an oil flush.

There are many things this COULD be.

First is what year is your truck? That makes a difference on diagnosis.

Possibilities:
U-Joint
Drive Flanges
It's a 91-92
Worn pinion bearings
Bad suspension bushings
Broken motor mount
Broken transmission mount

 

[Desert Dino]

There are many things this COULD be.

First is what year is your truck? That makes a difference on diagnosis.

Possibilities:
U-Joint
Drive Flanges
It's a 91-92
Worn pinion bearings
Bad suspension bushings
Broken motor mount
Broken transmission mount

He gets the noise going from D to R or visa versa, this is U-Joint drive shaft most of the time

 

[BILT4ME]

He gets the noise going from D to R or visa versa, this is U-Joint drive shaft most of the time

I agree MOST of the time.

He asked what it COULD be. It could also be NOTHING if it's a 91-92 year, as they don;t have the viscous coupler that acts as a cushion to silence some of the noises. You are ASSUMING this is a new noise for him.

 

[Elfego]

Do not flash the trans!!! just drain it and add good quality oil Dexron III drive and change again until looks ok

10years?? i do it every year all fluids and after 6 months engine oil + filter only every 2 years brake fluid + steering oil

Yup. Engine oil/filter, break fluid...the essentials are changed accordingly. Transmission and t case have not seen new oil in a while.

 

[Elfego]

There are many things this COULD be.

First is what year is your truck? That makes a difference on diagnosis.

Possibilities:
U-Joint
Drive Flanges
It's a 91-92
Worn pinion bearings
Bad suspension bushings
Broken motor mount
Broken transmission mount

96.

Just did a front axle rebuild and everything looks good.
Front diff oil was drained and new was added yesterday.

 

[Desert Dino]

I agree MOST of the time.

He asked what it COULD be. It could also be NOTHING if it's a 91-92 year, as they don;t have the viscous coupler that acts as a cushion to silence some of the noises. You are ASSUMING this is a new noise for him.

Yes new noise he drives the rig for 10 years all ready

 

[BILT4ME]

96.

Just did a front axle rebuild and everything looks good.
Front diff oil was drained and new was added yesterday.

Did you do the work yourself or pay someone else to do the work?

Yes, it could be U-joints, however, if it started immediately following a front axle rebuild, I would also look at wheel bearing adjustment, proper grease application to spindles and birfs, as well as front driveshaft attachment IF it was removed during the rebuild (It does not need to be unless the differential has been removed.)

 

[Elfego]

Did you do the work yourself or pay someone else to do the work?

Yes, it could be U-joints, however, if it started immediately following a front axle rebuild, I would also look at wheel bearing adjustment, proper grease application to spindles and birfs, as well as front driveshaft attachment IF it was removed during the rebuild (It does not need to be unless the differential has been removed.)

Dad and I. Clunk noise has been there since way before the rebuild. Probably a year now. It's more like a heavy metal hitting another metal instead of a clunk.
To my knowledge, bushings have been getting replaced one by one over the past few years.
I'll check the driveshaft tonight after work and try to record a video of the noise. Definitely needs new oil in the trans though.

I now am looking at all these things since it was passed down from my parent's daily family car to me.

 

[COYS]

Mine makes this clunk noise too, but only when truck is warmed up. I have a factory fresh rear drive shaft and a Wits' End or Landrover whatever front DC.

 

[BILT4ME]

Yes new noise he drives the rig for 10 years all ready

From his very first post:
"I’ve had this clunk noise for quite some time now."

To the OP:
Since you went through the front end an rebuilt it and did not have any true results, and you state: "It's more like a heavy metal hitting another metal instead of a clunk."
Assuming it's not the "normal" first to reverse clunk (because it takes up ALL driveline slack from one extreme to the other....)

If you don't get the high pitched "ding" when you do it, then it's less likely to be U-Joint.

Then I would lean toward:
Transfer case play from input to output
Transfer case play front output to rear output
Possible loose pinion bearings front and/or rear
Check the transmission and engine mounts for play

Check the amount of rotational play (by hand with the engine off, wheels chocked, trans in neutral, T-Case in Hi) by grabbing the front DS and twisting from full left to full right and estimate the TOTAL number of degrees of rotation betweeen loose play, light contact play, and hard stop. Do the same with the rear DS.

Loose play will be free rotation between the slightest contact internally. This will be the pinion to ring clearance. This should only be 1-3 degrees.
Light contact will be make the contact to one side of the ring, then rotate more until you feel the next resistance. This could be the front drive flanges to the axle to the ring gear OR it could be the clearance within the transfer case, whichever is LEAST. This will be about 10-15 degrees total from left to right.
Hard stop will be as hard as you can twist by hand left to right. This will be a few more degrees, 15-20 degrees tops. If you are above these estimates, you MAY have worn drive flanges, worn pinion bearings, or worn internals in the T-Case.

Then you work through them one set at a time starting with cheapest and easiest. Drive flanges.

Check your FSM for more info on each of these and acceptable tolerances.

Also, don't forget to grease your u-joints and yokes. Do this when the drive line is UNLOADED as I described above.
Hard stop

 

[BILT4ME]

Also check sway bar mounts. Sometimes they break and will create a clunk noise going from F to R.

 

[Tools R Us]

There are lots of things that it could be, most common is dry drive shaft splines.

 

[Elfego]

From his very first post:
"I’ve had this clunk noise for quite some time now."

To the OP:
Since you went through the front end an rebuilt it and did not have any true results, and you state: "It's more like a heavy metal hitting another metal instead of a clunk."
Assuming it's not the "normal" first to reverse clunk (because it takes up ALL driveline slack from one extreme to the other....)

If you don't get the high pitched "ding" when you do it, then it's less likely to be U-Joint.

Then I would lean toward:
Transfer case play from input to output
Transfer case play front output to rear output
Possible loose pinion bearings front and/or rear
Check the transmission and engine mounts for play

Check the amount of rotational play (by hand with the engine off, wheels chocked, trans in neutral, T-Case in Hi) by grabbing the front DS and twisting from full left to full right and estimate the TOTAL number of degrees of rotation betweeen loose play, light contact play, and hard stop. Do the same with the rear DS.

Loose play will be free rotation between the slightest contact internally. This will be the pinion to ring clearance. This should only be 1-3 degrees.
Light contact will be make the contact to one side of the ring, then rotate more until you feel the next resistance. This could be the front drive flanges to the axle to the ring gear OR it could be the clearance within the transfer case, whichever is LEAST. This will be about 10-15 degrees total from left to right.
Hard stop will be as hard as you can twist by hand left to right. This will be a few more degrees, 15-20 degrees tops. If you are above these estimates, you MAY have worn drive flanges, worn pinion bearings, or worn internals in the T-Case.

Then you work through them one set at a time starting with cheapest and easiest. Drive flanges.

Check your FSM for more info on each of these and acceptable tolerances.

Also, don't forget to grease your u-joints and yokes. Do this when the drive line is UNLOADED as I described above.
Hard stop

While lifted or on the ground? Just tried on the ground and drive shafts are sturdy. Rear has a bit of play, but they definitely look dry at the U Joints

 

[BILT4ME]

While lifted or on the ground? Just tried on the ground and drive shafts are sturdy. Rear has a bit of play, but they definitely look dry at the U Joints

On the ground.

If you do the chicks and neutral like I stated that unloads the drive line.

You should grease your u-joints as well as your slip yokes. Be careful to not overpressure your slip yokes and depress the little ball in the center of the zerk after greasing to allow pressure to bleed off.