# Thump and CLunk noises at back while moving



## KLL (Dec 2, 2005)

Dear friends
While accelerating gently from stop, shifting from 1 to 2,it makes a CLunk/Thump noise. OR i feel something is causing a Thump noise. Like some body bumped at back, sometimes this is faint, some times so evidentç

While cruising on 40 miles or so, when i let it cruise own by own and than when i step on the gas gently it makes a clung noise especialy descending on a slope on road.

when car is loaded and all seats are occupied, all these sounds are faint or there are no sounds at all.

Could you make comment according to your experiences on your cars?

Diff is making no noise on road no whining etc, on all gears no shifting noise or hard shifting feeling. Just making a thump at start.

Pelase help.

ps. on a 4runner forum everybody were applying grease oil to U joints...

Pss. i checked drive shaft by trying to turn it by hand, it seemed little bit loose. it makes a clunk when i try turn it.


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## dvdswanson (Nov 6, 2005)

check the bushings to the axle and sway bars.


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## KLL (Dec 2, 2005)

well, actually we checked. repairman told me same thing. he said that bushings are so soft /loose and he pulled the axle while car is on lift, i saw that he can move the whole assembly. then i checked another car, a small suv by suzuki, it was rock solid.

are those really have effect on shifting noise? i was thinking that these could change the ride comfort, stability and handling.


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## KLL (Dec 2, 2005)

dear friends do you have any other ideas to solve my problem?


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## Zilverado (Sep 25, 2002)

KLL said:


> ...ps. on a 4runner forum everybody were applying grease oil to U joints...
> 
> Pss. i checked drive shaft by trying to turn it by hand, it seemed little bit loose. it makes a clunk when i try turn it.


I was going to suggest u-joints as well. Although it they are clunking that badly, I would suggest they are beyond a simple greasing and need to be replaced.

If you can move the u-joint back and forth (rotationally), I'd say it's in need of replacing. These should have no movement in the u-joint itself. There may be some lash (slop) in the pinion of the differential, so make sure watch to see what is actually moving. You definitely do not want to have a u-joint come apart on you as your cruising down the highway...


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## KLL (Dec 2, 2005)

i went to another guy, who is specialized on drive shafts, he told me that everything is ok with U joints but may need some lubing. than he tried the ar while braking simultaneously. I realized that wheels are moving back and forth evidently. I think as sugessted , bushings of arms gone bad. So they need to be replaced.


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## 97Path (Jun 18, 2004)

KLL said:


> i went to another guy, who is specialized on drive shafts, he told me that everything is ok with U joints but may need some lubing. than he tried the ar while braking simultaneously. I realized that wheels are moving back and forth evidently. I think as sugessted , bushings of arms gone bad. So they need to be replaced.


Gladl you found out what was wrong. I had the same symptoms as your pathfinder and it wound up being the diff. It was completely destroyed.


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## KLL (Dec 2, 2005)

i replaced bushings. well, actually thump noise still exist at back during acceleration, but it is faint now. so it means that bushings were just amplifying the feel. car handles better now, and first gear to second gear change is better but there is still same clunk noise during braking and right after stopping.


i went to a differential service shop which is able to service LSD, then i went to a shop for checking shaft, both seemed ok to them.

i still think that the connection point of shaft and diff is loose, or went bad. a U joints are not loose btw. and no problem or sound durign cruising.

i think transmission is littl ebi tharsh on first gear, so this makes shaft force diff to move. so because of loose elements i hear and feel that thump.

any ideas?


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## KLL (Dec 2, 2005)

an update.

I replaced stabilizers at back (z rods) and used lots of grease to front shaft and removed rear shaft and applied lots of grease, where it enters transmission. now it is almost gone.


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## ya472 (Feb 10, 2010)

2001 Pathfinder SE, 5 speed, 120km (72k miles)

Rear axle thump very evident;
1) shifting lower gears
2) decelerate and then accelerate sharply
3) stopping on an uphill grade by applying the parking brake, and vehicle actually 'rolls' backward.

Seems to me that I have bushing problems.

However, as I increase speed on the hiway, there is an increasingly loud whine coming from the rear differential area in 2wh-drive.

I am concerned that the pinion is misaligned, or maybe the loose bushings are causing a driveshaft misalignment and vibration.

I still need a complete diagnosis, but have been resisting the expense of taking the truck to a garage.


Any helpful thoughts and comments?


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## IanH (Feb 11, 2003)

i have had a thump since I brought my 2003 in 2004. Dealer said it was fine, hasn't changed much so I guess its just drivetrain lash.


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## Breemania (Feb 14, 2010)

*Dear YA*

Oh Sh-t! 
Dude I had that problem on my 300ZX Turbo, Checked everything. The whine will get louder and louder over time. It finally got very loud on the expressway. Bottom line it was the rear end, I had to replace the rear. The dealer wants a ton of money for a new one, which is a rebulit. Your best bet is to find out what rear you have and travel the junk yards and grab one. One thing I did when examing the rears was to remove the fill plug "Top One"
to check the color of the oil in the rear, just stick your finger in there. Bring a 3/8 rachet and extension to remove fill plug, I think it's 3/8's might be a 1/2" its been a while, check on your rear end. Actually 6 years and the rears still like new so I got a good one. Good luck. 

:givebeer:


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## ya472 (Feb 10, 2010)

*Update to thump and whine noise.*

2001 Pathfinder SE, 3.5 l, 5-speed, 4x4

Finally got under the SUV and wiggled the REAR upper control arms. I could move them about half an inch, without much effort.

Went to the jobbers and then to the dealer parts and the guy strongly suggested replacing both upper arms (a bushing at each end) at a $ 175 (Canadian) each. The bushing cost $22 x 2 per arm, total $100 w/taxes.

I ordered the bushings, supported the rear body of the Pathy and let the rear suspension hang at full extension. Using a huge flex-bar, I was able to snap the bolts free, drop the arms (no rust @ 123,000km) and examined the bushings. The rubber was toast !

Using a sawzall, I carefully cut the thin outer sleeve and slid the bushing out. I took the arms and the new bushings to a semi-truck dealer shop, and the guy popped the bushings in, @ NO Charge. 

The truck runs like new, quiet and no jerky startups or shifts.

Total cost: my time, tools and $100.


Apparently the previous owner was towing a large boat, so maybe the bushing rubber was too soft ?


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## IanH (Feb 11, 2003)

has the whine gone as well ??

Since mine has been like it since 25,000 miles and just over a year old I haven't worried about it.


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## ya472 (Feb 10, 2010)

*Yes, all the whining stopped... including me.*



IanH said:


> has the whine gone as well ??
> 
> Since mine has been like it since 25,000 miles and just over a year old I haven't worried about it.


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The whine is caused by the misalignment of the driveshaft. 

You might not worry about it, but the driveline is out of balance, and will cause excessive wear on your transfer case output bearing, the u-joint bearings and the differential input bearing.

My truck drives like new now. There is no whine, or clunking when shifting, and no clunking when going over speed bumps or potholes, therefore offroading should be more fun. 

The rubber in the bushing was way too soft for this application. I am hoping the Nissan replacement bushings last more than 25,000 miles !!!!!!


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## IanH (Feb 11, 2003)

Thanks.
I didnt write that well.
mine just thumps when you engage a gear from neutral. Was interested in the whine problem. Will inspect mine when I am under there next !!!


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## Ronald Umland (Apr 12, 2020)

KLL said:


> Dear friends
> While accelerating gently from stop, shifting from 1 to 2,it makes a CLunk/Thump noise. OR i feel something is causing a Thump noise. Like some body bumped at back, sometimes this is faint, some times so evidentç
> 
> While cruising on 40 miles or so, when i let it cruise own by own and than when i step on the gas gently it makes a clung noise especialy descending on a slope on road.
> ...


If it dont do it when turning its probably struts or motor mount


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## rogoman (Dec 16, 2004)

The original post is about 13 years old. The OP probably either has fixed it by now or sold the vehicle. Please *DO NOT* highjack something that's that old. Just start a new thread!!


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## smj999smj (Jan 1, 2006)

rogoman said:


> The original post is about 13 years old. The OP probably either has fixed it by now or sold the vehicle. Please *DO NOT* highjack something that's that old. Just start a new thread!!


It's his first post, so, I think we can cut him a break...THIS time... LOL


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