Drivetrain noise solved (or, how dumb am I)?

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Cal_Gary
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Drivetrain noise solved (or, how dumb am I)?

Post by Cal_Gary »

Most of you know I've been pushing on with my M37 project since July 2004. Having had transmission issues, clutch issues, wiring, starter (hey, what HAVEN'T I had to deal with)?! Anyway, I had one pesky drivetrain rattle that I've been unable to resolve, until last Sunday. Since this rattle only appeared when the M was in motion, I was left with no choice but to drop the front drive shaft (transfer case side only, and I use lockout hubs), pull both back tires off and put the rear on two jack stands (with the jack acting as the fail-safe support along with both tires laid flat under the rear crossmember). After securing each drum with two lug nuts, I started the M and went through all four forward gears, and there it was: ting, ti-ting, ting....

Leaving it idling in 4th gear, I grabbed my creeper and went below:
Clutch and release bearing-ok
Transmission-ok (freshly rebuilt)
Transfer case-ok
Rear diff-ok

The culprit? The right-rear inner corner floorboard bolt is too long and the transfer case shift linkage is ting, tinging against it! Oh how foolish (and relieved I am). I backed out that bolt-silence! Buttoned everything back up and took a 3-mile test drive-no problem!

I am relieved to have solved this one without springing for another transfer case (which I just passed on one locally, rolling the dice that I'd find something else wrong instead).

Lessons learned:
1. Don't overlook the small details;
2. Don't let your project beat you-stay after it and think it through when you have a tough problem-you'll eventually get it figured out! :D
Gary
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rixm37
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Post by rixm37 »

Way to go Gary !
It's amazing how many times it is something really simple that is the culprit ! It's hard not too think huge problem at first!! And VERY frustrating. Glad you passed on the other t-case.
1952 M37
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1942 Chevy G506
Cal_Gary
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Post by Cal_Gary »

Thanks! Credit should go to my spouse of 27 years who took the earlier test drive and said "it sounds like something rubbing, to me..." and of course I blew her off, being the "expert" in the family when it comes to old HMVs--she's laughing now (and relieved that we didn't have to shell out big bucks for a transfer case)!
Gary
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m-37Bruce
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I Think I Said It Before

Post by m-37Bruce »

Your Bride of 27 years sounds like a "Keeper"!
Bruce,

1953 M-37 w/ow

Retired Again

Keep Em Rollin'

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T. Highway
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Post by T. Highway »

Way to go Gary, It looks like you made a good choice 27 years ago. :wink:
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Post by Cal_Gary »

Indeed I did-thanks Guys! :D
Gary
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HingsingM37
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Post by HingsingM37 »

Glad to hear it was a simple fix. Last summer I feared I had a rod knock only to find my front xfer case lever rattling against the trans cover, I did not have my shift lever boot installed yet :)
David
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Post by Cal_Gary »

You're right, David,
All those little noises are spooky when you first get it on the road (as I now am) with the trips getting stretched a little longer and longer as I gain faith that I'm not going to be stranded on the side of the road.

My 2/4 hi/low shifter bracket was so worn out I ended up using a front leaf-spring pin and cut the new bushing in half to do the repair. The bushing fits inside the shifters perfectly, and using the spring pin allows you to use a locking nut to secure it instead of a cotter pin and washer. This keeps the shifters from slopping around. Snug = no rattling around. I'd lose points by the HMV judges but the field mod works as I intended....
Gary
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