Author Topic: Manual Transmission noise  (Read 5007 times)

johnk

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Manual Transmission noise
« on: April 03, 2014, 16:31:58 »
Hello everyone,

I purchased my 68 280sl with a manual transmission two weeks ago. When I test drove it I immediately noticed the mid level whine after I shifted and while stepping on the gas. The noise goes away after you get up to full speed in each particular gear. and seems directly proportionate to the stress on the transmission after shifting. This was my first ride in one of these cars so I am not 100% certain how it should sound, but it reminded me of when I last drove a car from the 30's.

The noise is definitely noticeable. Even my sister-in law wondered how old the car was after shifting it. Any ideas if this could be the throw-out bearing or something else other than its been too long since I drove a car from the 60's?

Thanks
JohnK



John Krystowski
Avon Ohio
1968 Euro 280sl under restoration
2016 Jag F-Type R sold june 2021
1950 Alfa Romeo 6C 2500 SS For sale
2008 E350
2007 GL 450
2019 BMW 540

johnk

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Re: Manual Transmission noise
« Reply #1 on: April 03, 2014, 16:42:16 »
Sorry forgot to add:

The transmission shifts smoothly and doesn't appear to make any other noises. I have not checked or replaced the oil yet but plan on doing that this weekend. It may be a while before I can drive it again to see if new oil helps so I thought I would pose the question to the forum first.

thanks
Johnk
John Krystowski
Avon Ohio
1968 Euro 280sl under restoration
2016 Jag F-Type R sold june 2021
1950 Alfa Romeo 6C 2500 SS For sale
2008 E350
2007 GL 450
2019 BMW 540

George Des

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Re: Manual Transmission noise
« Reply #2 on: April 03, 2014, 18:59:03 »
Just make sure you are running ATF and not regular gear oil. Yes, the manuals use automatic transmission fluid not gear oil.

George Des

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Re: Manual Transmission noise
« Reply #3 on: April 03, 2014, 18:59:53 »
Just make sure you are running ATF and not regular gear oil. Yes, the manuals use automatic transmission fluid not gear oil.

ja17

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Re: Manual Transmission noise
« Reply #4 on: April 03, 2014, 20:33:09 »
These transmissions are usually very smooth and quiet. Most likely low on fluid or a damaged bearing.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

johnk

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Re: Manual Transmission noise
« Reply #5 on: April 03, 2014, 22:08:35 »
Thanks Joe,

I will start with replacing the ATF. If it is a bearing, do you think it would be the throw-out bearing? I guess I will see if I have to pull the transmission.

John
John Krystowski
Avon Ohio
1968 Euro 280sl under restoration
2016 Jag F-Type R sold june 2021
1950 Alfa Romeo 6C 2500 SS For sale
2008 E350
2007 GL 450
2019 BMW 540

jeffc280sl

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Re: Manual Transmission noise
« Reply #6 on: April 04, 2014, 01:09:01 »
I don't think noise from the throughout bearing is subject to the kind of loads you describe.  It engages and disengages the clutch plate.  It is under load so to speak when doing these functions.  Once the clutch is engaged there should be no particular load to cause noise. 

I rebuilt my manual transmission.  There is lots of help here if you decide to go this route.  Challenging job.  I remember getting something wrong and it would not stay in third gear.  Had to tear it all down again and start over.  It is perfect now. 

johnk

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Re: Manual Transmission noise
« Reply #7 on: April 04, 2014, 16:10:53 »
Thanks Everyone. I am sure I will have more questions if changing the ATF does not work. Any recommended type of ATF?

John K
John Krystowski
Avon Ohio
1968 Euro 280sl under restoration
2016 Jag F-Type R sold june 2021
1950 Alfa Romeo 6C 2500 SS For sale
2008 E350
2007 GL 450
2019 BMW 540

ja17

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Re: Manual Transmission noise
« Reply #8 on: April 05, 2014, 20:31:09 »
Dextron or its replacement seems to be the most widely used. Probably not critical on the standard transmissions as long as it is ATF.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback