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Loud metallic clunk every time I accelerate

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Old 11-03-2013, 04:26 AM
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Default Loud metallic clunk every time I accelerate

I have a loud metallic clunk every time I lift my foot off the accelerator and then re-accelerate. Also have have a high frequency drive-line vibration present starting at 23 mph to 30 mph,.....then it fades until 49 mph and again at 70 mph. Both driveshafts are newly rebuilt and re-balanced and care was taken to insure that the driveshafts went back together the same way they came apart,...and back on the truck in the same position that they came out.

Wondering if anyone else has had this clunk, and if it might be related to my mystery driveline vibration.

Brian in Austin
 
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Old 11-03-2013, 05:57 AM
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Originally Posted by bcolins
I have a loud metallic clunk every time I lift my foot off the accelerator and then re-accelerate. Also have have a high frequency drive-line vibration present starting at 23 mph to 30 mph,.....then it fades until 49 mph and again at 70 mph. Both driveshafts are newly rebuilt and re-balanced and care was taken to insure that the driveshafts went back together the same way they came apart,...and back on the truck in the same position that they came out.

Wondering if anyone else has had this clunk, and if it might be related to my mystery driveline vibration.

Brian in Austin
The autobox suffers from a torque converter failure problem which may be an issue.

Gearbox and Torque Converter Problem - Land Rover Forums : Land Rover and Range Rover Forum
 
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Old 11-03-2013, 06:37 AM
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Motor mounts worth a look.
 
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Old 11-03-2013, 08:42 AM
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When did you last service your tranny and t/case, did you inspect both drain plugs for metal?
When your front shaft was rebuilt, did they also replace the centering ball?
 
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Old 12-22-2013, 09:22 AM
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Originally Posted by Disco Mike
When did you last service your tranny and t/case, did you inspect both drain plugs for metal?
When your front shaft was rebuilt, did they also replace the centering ball?
Mike, I've done two tranny drain and refills within the last 2-3,000 miles. (as mentioned in my other thread about the hanging 1-2 and 2-3 shifts), but have not done a T case service. There was no metal on the tranny drain plug. I bouught this truck about 9 month ago,..and generally do all my own work. ( I'm also a prior service manager for a dealer and owned a small Euro performance car restoration and resale business for 20 years).

I rebuilt my driveshafts using the preferred Neapco joints and Centering ball, then had them both re-balanced as I had original joints still and a driveline vibration (Driveshaft rebuild did NOT cure this) I plan on getting underneath the truck soon while a friend moves the shift lever from D to R and see if I can spot the clunk. Wondering if I have worn splines on one of my shafts.

I noticed that when I pulled the rear shaft, that the Emergency brake drum fasteners were all a bit loose, and that when I put the drum back on,......it was NOT a Snug/ tight fit over the fastening studs,....wondering if the holes in the drum might be wallered out from the fasteners not having been properly tightened by someone.

I also noticed yesterday, when I lightly pull up on the E-Brake lever while moving, that there is a LOT of vibration coming up from the eBrake drum,.....which seems to confirm my thoughts about the ebrake drum holes being enlarged and allowing the ebrake drum to be off center causing my driveline vibration perhaps.

any thoughts?

Brian
 

Last edited by bcolins; 12-22-2013 at 09:30 AM.
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Old 12-22-2013, 01:14 PM
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Change the transfer case fluid or at least top it off. I had the exact same "clunk" when taking my foot off or putting foot back on. My tcase was a quart or two low. Use 85w140 or follow this thread:

https://landroverforums.com/forum/di...ictures-27159/

Can't help with your vibration. Is the rotoflex that connects the rear shaft to the rear diff worn or cracking?
 

Last edited by caymandrew; 12-22-2013 at 01:18 PM.
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Old 12-22-2013, 02:31 PM
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I would look at the roto flex as mentioned may not hurt to just replace it as you do not know how old it is. Also as mentioned the motor and transmission mounts, see if you can tighten them up. I had a weird vibration awhile ago, my mechanic and I loosened up all the mounts pushed the whole engine/tranny assembly all the way to the right then to the left make measurements and then centered the assembly. tightened everything back up and the vibration went away.
 
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Old 12-22-2013, 10:09 PM
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Originally Posted by bcolins
I have a loud metallic clunk every time I lift my foot off the accelerator and then re-accelerate. Also have have a high frequency drive-line vibration present starting at 23 mph to 30 mph,.....then it fades until 49 mph and again at 70 mph. Both driveshafts are newly rebuilt and re-balanced and care was taken to insure that the driveshafts went back together the same way they came apart,...and back on the truck in the same position that they came out.

Wondering if anyone else has had this clunk, and if it might be related to my mystery driveline vibration.

Brian in Austin

My rig suffers the exact same symptoms at about the same speeds. Looks like I have a lot of things to look into.
 
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Old 12-23-2013, 06:58 AM
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I'm going with.....................still your driveshaft. did you do centering ball ?

Mine clunked for ages, miles. Then once driveshaft met it's final doom and got totally rebuilt, the transition between acceleration/ deceleration finally became smooth and "noiseless".
 
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Old 12-23-2013, 07:18 AM
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the noise you are hearing is it the sound of the drive line tightening up, like every all wheel drive or is it an actual metal banging. All LR have a sound when you load and unload the drive line. The vibration could be a different problem all together
 


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