Shifting from 2nd to 3rd runs into reverse

1959 - 1978, M151, M151A1, M151A2, Technical questions and discussions, regarding anything related to the M151.
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sjtrucks
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Shifting from 2nd to 3rd runs into reverse

Post by sjtrucks » Sun Sep 13, 2020 12:57 am

Hi,

Just got this M151A1 that runs pretty well mechanically except when shifting from 2nd to 3rd, it wants to go to reverse. No such problem shifting down from 4th to 3rd. My mechanic things the detent spring that helps it "find" neutral might be bad so it doesn't find neutral when shifting up. Was wondering if anyone has run into a similar issue? For now, double clutching seems to do the trick.

Thanks!
- SJ

1950 Willys CJ3A
1966 Ford M151
1997 Toyota LandCruiser


hambone
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Re: Shifting from 2nd to 3rd runs into reverse

Post by hambone » Sun Sep 13, 2020 6:35 am


sjtrucks
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Re: Shifting from 2nd to 3rd runs into reverse

Post by sjtrucks » Sat Oct 03, 2020 8:11 am

Thanks - it is in the shop today, and I passed on the repair instructions to them. Again, big thanks for pointing in the right direction 🙂
- SJ

1950 Willys CJ3A
1966 Ford M151
1997 Toyota LandCruiser

markrdje
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Re: Shifting from 2nd to 3rd runs into reverse

Post by markrdje » Sat Oct 03, 2020 4:36 pm

I use 3 separate motions--upward movement to move shifter to neutral, move shifter horizontal motion, back and forth quick to up to 3rd gear position.No speed shifting
change user name to mark

sjtrucks
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Re: Shifting from 2nd to 3rd runs into reverse

Post by sjtrucks » Sun Oct 04, 2020 6:47 pm

markrdje wrote:
Sat Oct 03, 2020 4:36 pm
I use 3 separate motions--upward movement to move shifter to neutral, move shifter horizontal motion, back and forth quick to up to 3rd gear position.No speed shifting
Thanks, will try that too.
- SJ

1950 Willys CJ3A
1966 Ford M151
1997 Toyota LandCruiser

sjtrucks
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Re: Shifting from 2nd to 3rd runs into reverse

Post by sjtrucks » Mon Oct 12, 2020 3:06 pm

hambone wrote:
Sun Sep 13, 2020 6:35 am
This may help. Hambone
https://web.archive.org/web/20040107075 ... vgate.html
When opening up the tranny cover - is there any preventative maintenance or parts that can be easily swapped out? Floor cover seals? Anything else? Thanks.
- SJ

1950 Willys CJ3A
1966 Ford M151
1997 Toyota LandCruiser

Bart1015
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Re: Shifting from 2nd to 3rd runs into reverse

Post by Bart1015 » Tue Oct 20, 2020 7:30 am

I had the exact same issue. I could get it to go into 3rd, but only when I was very carful to avoid the lever going into reverse.

My issue turned out to be the "plunger" located in the gearshift housing. The plunger actually had a deep groove cut in it from the spring loaded ball. I replaced the plunger, ball and spring and my issue totally went away.

Hope this helps.

The schematic showing the parts are in TM 9-2320-218-34-1 (August 1982)
Chapter 7-20
Page 7-83
Part #3 - Plunger
1942 VEP GPW, J-2 winch, BC-659, 1919a4
1945 GPW, 1943 MBT
Sold - 1967 M151a1, 1943 MB, M416
www.ToThePointPolygraph.com


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