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Thumping when rolling backwards
Thread Starter
8th Gear
Joined: Apr 2007
Posts: 8
Likes: 0
From: Smithtown New York
Thumping when rolling backwards
1973 L48 with 4 speed.
When I am rolling backwards with the transmission in reverse and the clutch in I hear a thumping sound from the transmission area.
If I have the clutch out (engaged), in reverse going backwards no thump.
If rolling backwards in neutral no thump.
Any advice appreciated.
When I am rolling backwards with the transmission in reverse and the clutch in I hear a thumping sound from the transmission area.
If I have the clutch out (engaged), in reverse going backwards no thump.
If rolling backwards in neutral no thump.
Any advice appreciated.
Burning Brakes
Joined: Mar 2008
Posts: 1,038
Likes: 39
From: Denver, CO
St. Jude Donor '08-'09-'10
stupid question but 4 speed auto or manual? does it only do it when the car is turned on, or have you tried in reverse with car off? triple checked tranny fluid level?
Thread Starter
8th Gear
Joined: Apr 2007
Posts: 8
Likes: 0
From: Smithtown New York
Its a 4sp manual.
I only noticed the sound with the engine running. I don't remember hearing it when rolling backwards with the engine off.
Tranny fluid was checked, level was ok.
I only noticed the sound with the engine running. I don't remember hearing it when rolling backwards with the engine off.
Tranny fluid was checked, level was ok.
Burning Brakes
Joined: Sep 2005
Posts: 1,198
Likes: 0
From: staten island new york
St. Jude Donor '10
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Thread Starter
8th Gear
Joined: Apr 2007
Posts: 8
Likes: 0
From: Smithtown New York
I checked all of the above suggestions, including looking for the cat. Everything checked out ok. I finally opened up the transmission and found a couple of chipped teeth on the reverse idle gear. Of course the guy at the tranny shop said the idler gear for the muncie m20 has been discontinued. But atleast now we know where that sound was coming from. Thanks for the help.
Racer
Joined: Nov 2009
Posts: 423
Likes: 7
From: Utah
Revearse Idler Gear
A quick search on google shows a few that sell them. I didn't check to see if it's still in stock, but it's still listed ($48).
http://www.tbtrans.com/muncie_4_spee...uncie_gearsets
Good thing about the cat
http://www.tbtrans.com/muncie_4_spee...uncie_gearsets
Good thing about the cat
Melting Slicks
Joined: Dec 2006
Posts: 2,669
Likes: 3
From: Kingston Ontario
I checked all of the above suggestions, including looking for the cat. Everything checked out ok. I finally opened up the transmission and found a couple of chipped teeth on the reverse idle gear. Of course the guy at the tranny shop said the idler gear for the muncie m20 has been discontinued. But atleast now we know where that sound was coming from. Thanks for the help.
Time for a trany overhaul with a shift kit upgrade!Or maybe that new 5 speed? You been power shifting?
Gotta' like a forced upgrade! " Dear, I have no choice but to change the transmission! Oh well... "
Let us know the outcome.
