The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-19-2008, 12:10 AM   #1
samwise68
FarmBoy.
 
samwise68's Avatar
 
Join Date: Feb 2005
Location: Rhinelander, WI
Posts: 1,103
Bad shifting noises...

Hey all.

My ol' 3 speed has been acting up lately. When I downshift from 3rd to 2nd, there is an odd grinding sound.

I figured it was the clutch not being adjusted right. so, adjusted the clutch, it's still there.

If i take my time shifting, and let it spin some, it seems to slide right on home.

We're kind of thinking it's a pilot or throw out bearing, and when it's allowed to spin between shifting, it centers itself. Sloppy input shaft, or bad detents also were considered.

any comments, advice, previous experience, 2 cents would be great on this.

thanks in advance all!

-Sam.
__________________
1969 GMC C1500. long fleet.
307. 3 on the tree. 3.07 gears.
Oliver green. Bent and bruised. Daily Driver.

Quote:
Screw patina... it's a beater...Beaters are cool.
my build thread - Project Homebrew:
http://67-72chevytrucks.com/vboard/s...d.php?t=242993
samwise68 is offline   Reply With Quote
Old 05-19-2008, 12:26 AM   #2
Wrenchbender Ret
Registered User
 
Join Date: Oct 2005
Location: Overland Park, Ks.
Posts: 5,228
Re: Bad shifting noises...

The syncronizers are bad. 2nd & 3 rd gears have syncros. that adjust the speed of the shaft before it engauges.
Wrenchbender Ret is offline   Reply With Quote
Old 05-19-2008, 12:46 AM   #3
samwise68
FarmBoy.
 
samwise68's Avatar
 
Join Date: Feb 2005
Location: Rhinelander, WI
Posts: 1,103
Re: Bad shifting noises...

thank you!

I thought it might be that, but was leaning towards something more clutch related.

alright. I have a spare 3 speed in a parts truck I'll pull soon.

Also, please forgive my amateurness, but, will driving it be an issue? heh. as in, is this sucker gonna grenade on me? or, if i drive nice (double clutch maybe?) it'll last for a little bit.

thanks again!

-Sam.
__________________
1969 GMC C1500. long fleet.
307. 3 on the tree. 3.07 gears.
Oliver green. Bent and bruised. Daily Driver.

Quote:
Screw patina... it's a beater...Beaters are cool.
my build thread - Project Homebrew:
http://67-72chevytrucks.com/vboard/s...d.php?t=242993
samwise68 is offline   Reply With Quote
Old 05-19-2008, 12:50 AM   #4
WorkinLonghorn
Senior Member
 
WorkinLonghorn's Avatar
 
Join Date: Dec 2006
Location: Studio City, Calif.
Posts: 2,883
Re: Bad shifting noises...

You can still drive it like that as long as you match speeds before shifting,ie,when downshifting rev it a bit,and when up-shifting,let it fall to where it will be after the shift.
__________________
'69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, stereo speakers, 2nd owner, Work-Truck supreme.
WorkinLonghorn is offline   Reply With Quote
Old 05-19-2008, 12:52 AM   #5
samwise68
FarmBoy.
 
samwise68's Avatar
 
Join Date: Feb 2005
Location: Rhinelander, WI
Posts: 1,103
Re: Bad shifting noises...

alright, thanks so much guys.

It's always easier to solve a problem when it's more than just my dad and I thinkin' on it.

That eases my mind on the driving as well, because thats usually how i drive when i'm not pretending my truck is faster than it really is, heh.

-Sam.
__________________
1969 GMC C1500. long fleet.
307. 3 on the tree. 3.07 gears.
Oliver green. Bent and bruised. Daily Driver.

Quote:
Screw patina... it's a beater...Beaters are cool.
my build thread - Project Homebrew:
http://67-72chevytrucks.com/vboard/s...d.php?t=242993
samwise68 is offline   Reply With Quote
Old 05-19-2008, 02:25 AM   #6
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: Bad shifting noises...

I agree, the syncros are probably getting worn... but, did you check the oil level?
Longhorn Man is offline   Reply With Quote
Old 05-19-2008, 06:28 AM   #7
samwise68
FarmBoy.
 
samwise68's Avatar
 
Join Date: Feb 2005
Location: Rhinelander, WI
Posts: 1,103
Re: Bad shifting noises...

I will be sure to check it tomorrow. I honestly can't remember if I filled it all the way up when I did the clutch or not. I know I filled it, but all the way...I'm uncertain. Will do!

Thanks for tips guys. any more ideas are always welcome, just in case I don't have to do a tranny swap. hah.

-Sam.
__________________
1969 GMC C1500. long fleet.
307. 3 on the tree. 3.07 gears.
Oliver green. Bent and bruised. Daily Driver.

Quote:
Screw patina... it's a beater...Beaters are cool.
my build thread - Project Homebrew:
http://67-72chevytrucks.com/vboard/s...d.php?t=242993
samwise68 is offline   Reply With Quote
Old 05-20-2008, 04:05 AM   #8
samwise68
FarmBoy.
 
samwise68's Avatar
 
Join Date: Feb 2005
Location: Rhinelander, WI
Posts: 1,103
Re: Bad shifting noises...

well. pulled the spare 3 speed. and that sucker is about half the length of the one in the truck. sooo. this could be a bit of an issue. Unless I take the driveshaft out of the truck as well, which would require a new carrier bearing, etc. a general freshening. Plus, I don't even know if that tranny is any good..let alone what kind it is, hah.

The plan for right now is to take it realllly easy, and hope she lasts for a while.

cross your fingers guys...this could get interesting.

-Sam.
__________________
1969 GMC C1500. long fleet.
307. 3 on the tree. 3.07 gears.
Oliver green. Bent and bruised. Daily Driver.

Quote:
Screw patina... it's a beater...Beaters are cool.
my build thread - Project Homebrew:
http://67-72chevytrucks.com/vboard/s...d.php?t=242993
samwise68 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:02 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com