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Backing up I heard a "clunk"

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jbowlby

jbowlby

Senior Member
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Backing up I heard a "clunk"

Yesterday when I backed the Midget into the garage I heard a dull "clunk". Anyone have words of advise before I start dismantling tomorrow?

This may be unrelated but while admiring it running down the road yesterday I also noticed that both rear wheels almost appear to "hop" and we have a slight vibration at 60 MPH.
 
Re: Backing up I heard a "clunk"

Loose U-bolts?
 
Re: Backing up I heard a "clunk"

...or loose dampers.
 
Re: Backing up I heard a "clunk"

daughter's bicycle?
 
Re: Backing up I heard a "clunk"

Check th' BEARINGS.

...just my immediate thought.
 
Re: Backing up I heard a "clunk"

Just a thought. I have a clunk that occurs when backing or braking after a prolonged period of driving. The statement about dampers got me thinking and I noticed a while back that the damper looked like it had been repaired and not attatched very well. I think I'll have a look at it tomorrow and I'll let you know what I find. Possibly if I find the culprit to my problem it will shed some light on yours.
 
Re: Backing up I heard a "clunk"

I agree check those spring mounting bolts. I must add with some hesitation that Mine would have a clunk backing up after running down the road (oil in tranny warmed up) shortly before the lay gear gave up on my smooth case.
Lets look at the other stuff before we go there.
 
Re: Backing up I heard a "clunk"

Check ALL of the rear suspension points, driveline, & mounts (u-bolts, links, mount points, shocks, u-joints, lug nuts, etc.) for play.

It sounds like you have excess play somewhere that is taken up slowly as you drive fwd... THEN when you reverse the loading (backing up) the play has to move in the opposite direction (thus the "clunk").

At the 50th one of the guys was hearing a "clunk" in the rear and we discovered that the upper contol arm (above the rear spring on a BugEye) bushing had migrated out of the arm, leaving about 1/4-inch of play in either direction. He couldn't hear the "clunk" (bad hearing, probably from years of open-top driving...), but his wife kept saying "What's that clunking noise?" on their 600 mile drive to LotO.

OF COURSE, it could be something nasty like a bad bearing in the rear end, or worn gears, but even a pumpkin swap is fairly easy & pumpkins in a variety of ratios are always popping up fairly cheap on eBay & Craig's.....
(Still, check all of the easy-to-access external stuff 1st!)

Hope this helps! :thumbsup:

-Bear-
 
Re: Backing up I heard a "clunk"

Another thought....
Check the trans mount & brakes too!

Could be that the trans shifts side to side as the driveline winds up...

OR could be something loose in the brakes...


One more thought, empty EVERYTHING out of the boot (aka: trunk) to be sure that an old can of "Fix-A'Flat" isn't rolling around.....
(I had a hard-to-find" noise once in a car that turned out to be the jack tipping back & forth.....)

-Bear-
 
Re: Backing up I heard a "clunk"

John-Peter:
"daughter's bicycle"

Too darn Funny!! :laugh:

-Bear-
 
Re: Backing up I heard a "clunk"

Everything is tight...I have about 1/2 inch back and forth play in each axle as well as 1/2 inch in the propeller shaft. so it looks like the differential. seems like alot.
Thoughts?
Im also not having any luck finding 90wt gear oil??? whats everyone using?
 
Re: Backing up I heard a "clunk"

jbowlby said:
Im also not having any luck finding 90wt gear oil??? whats everyone using?
Click to expand...

You probably won't find straight 90W. Use 85W90.
That should be available everywhere.
Jeff
 
Re: Backing up I heard a "clunk"

jbowlby said:
Everything is tight...I have about 1/2 inch back and forth play in each axle as well as 1/2 inch in the propeller shaft. so it looks like the differential. seems like alot.
Thoughts?
Im also not having any luck finding 90wt gear oil??? whats everyone using?
Click to expand...
You sure that yoke nut is tight, needs to be 200 foot lbs or something like that. I have had them back off some and give play and noise. 1/2 inch on the drive shaft doesn't seem so bad. Question, do you notice this more in 1st and reverse? Could be the cluster gear in the transmission having the teeth worn down a lot for first gear that is making this problem seem worse.
 
Re: Backing up I heard a "clunk"

Thanks for all of the suggestions...I still have the play but the "clunk" is gone I suspect that I had a loose hub on the drivers side.
 
Re: Backing up I heard a "clunk"

Down here in Johannesburg

Once going very slowly backwards I heard a clunk when I put on the brakes. Oh dear a broken spring. If you are replacing anything make sure you replace one of whatever on both sides.
 
Re: Backing up I heard a "clunk"

Jack it up. put the emer brake on and turn the drive shaft both ways by hand.

Should let you know where the slop is, might be as simple as a worn u joint.
 
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