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 > General Truck Forums > Engine & Drivetrain

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 04-02-2018, 08:31 PM   #1
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
1972 C10 2wd M20 wont go into gear

Hello. Working on maintaining a 72 c10 we pulled from a field last summer. All has been good. Redid brakes, lines and all. Now the truck will not go into gear. Seems to be stuck in neutral. With or without clutch it will not go into gear. Pulled shifter up and out and it seem,s to be fine.

Has lube/oil/grease on it and does not seem to be broken. Can place back into top of tranny without a problem.

Have not pulled inspection cover as we have to pull that crossmember it seems. Which means grind down all of those rivets.

Any hints, tips tricks to try before we do all of that? Side of tranny is so covered in oil,grease and dirt it will take a week to get to the bolts.

help?
Larry
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-02-2018, 08:40 PM   #2
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M20 wont go into gear

Leave it shut off, clutch engaged and try it in each gear while trying to push the truck back and forth.
geezer#99 is offline   Reply With Quote
Old 04-02-2018, 09:40 PM   #3
Alex V.
Registered User
 
Alex V.'s Avatar
 
Join Date: Mar 2013
Location: Campbellsville, KY
Posts: 880
Re: 1972 C10 2wd M20 wont go into gear

Quote:
Originally Posted by geezer#99 View Post
Leave it shut off, clutch engaged and try it in each gear while trying to push the truck back and forth.
This. ^
__________________
Alex V.
------
1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs.

1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue.
Alex V. is offline   Reply With Quote
Old 04-02-2018, 10:42 PM   #4
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

Ok. Tried that. Nuthin.
What would have meant if it did go into gear?
What does it mean that it did not?

It broke down and he could not get into gear going down the road. Maybe 30 mph.
So neutral it was and coasted into parking lot.
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-02-2018, 11:20 PM   #5
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M20 wont go into gear

Sometimes rocking it and trying to force it into gear lets it pop back in to place.
I guess you’ll need to dig deeper.
geezer#99 is offline   Reply With Quote
Old 04-02-2018, 11:27 PM   #6
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 21,365
Re: 1972 C10 2wd M20 wont go into gear

It sounds like you have a SM465 not a Muncie M20
__________________
Power Steering Box Adapter Plates For Sale HERE
Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE
Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE
Hydroboost Mounting Plates HERE
Captainfab is offline   Reply With Quote
Old 04-02-2018, 11:38 PM   #7
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

It says m20 on glove box.
Could it be shot?
90k miles.
Attached Images
 
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-02-2018, 11:56 PM   #8
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M20 wont go into gear

M20 is the RPO.
Not the trans type.
I think you might need to pull it apart.
geezer#99 is offline   Reply With Quote
Old 04-03-2018, 12:06 AM   #9
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

Damn dangit dagnabbit.

Any tips or hints? Support engine with floor jack.
Grind, chisel, drill out rivets for crossmember.
Drop driveshaft.
Use tranny jack on tranny to lower.

Is that about it? Best way to deal with rivets?
Heard using a cut off wheel/angle air grinder to
X them and then is air chisel to chisel for 4 pie shaped pieces was not bad.
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 01:00 AM   #10
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M20 wont go into gear

You don’t need to remove the crossmember to pull the tranny.
You need to pull the shifter out, unbolt the tranny hump, pull the driveshaft, unbolt the tranny and slide it back and remove it. Removing the hump gives you lots of room to work and room to slide the tranny back.

I haven’t pulled one for years. Maybe captain fab or someone else can give you removal tips.
geezer#99 is offline   Reply With Quote
Old 04-03-2018, 01:12 AM   #11
mongocanfly
Senior Member
 
Join Date: May 2015
Location: Alabama
Posts: 6,492
Re: 1972 C10 2wd M20 wont go into gear

read thru this...http://67-72chevytrucks.com/vboard/s...d.php?t=322025
make sure the shifter slots are correct...
__________________
Mongo...aka Greg

1981 c30 lq9 nv4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598
1955.1 ls3 tr6060...(under construction)(on hold)
2013 gmc z71. (daily driver)
Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563

Last edited by mongocanfly; 04-03-2018 at 01:17 AM.
mongocanfly is online now   Reply With Quote
Old 04-03-2018, 08:53 AM   #12
Alex V.
Registered User
 
Alex V.'s Avatar
 
Join Date: Mar 2013
Location: Campbellsville, KY
Posts: 880
Re: 1972 C10 2wd M20 wont go into gear

Quote:
Originally Posted by ratman90 View Post
Ok. Tried that. Nuthin.
What would have meant if it did go into gear?
What does it mean that it did not?

It broke down and he could not get into gear going down the road. Maybe 30 mph.
So neutral it was and coasted into parking lot.
If it had shifted into gear(s) with the engine off, it would have indicated the problem is that the clutch wasn't releasing and the synchronizer was doing its job and preventing the gears engaging before they're meshed as to not grind.
__________________
Alex V.
------
1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs.

1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue.
Alex V. is offline   Reply With Quote
Old 04-03-2018, 09:08 AM   #13
jjzepplin
Senior Member
 
jjzepplin's Avatar
 
Join Date: Feb 2012
Location: Riverview Florida
Posts: 3,502
Re: 1972 C10 2wd M20 wont go into gear

Quote:
Originally Posted by mongocanfly View Post
read thru this...http://67-72chevytrucks.com/vboard/s...d.php?t=322025
make sure the shifter slots are correct...
This. Easiest and real common. I have seem the shifter bend in side the tranny too.
__________________
70 swb 4x4 406sbc 700r4 203/205 d60/14blt locker yadda yadda http://67-72chevytrucks.com/vboard/s...88#post6935688
72 Blazer 2wd conversion project "No Daggum Money" http://67-72chevytrucks.com/vboard/s...d.php?t=550804 3.73 posi-4-speed Saginaw-307-no budget build.
58 Belair http://67-72chevytrucks.com/vboard/s...d.php?t=756563
jjzepplin is offline   Reply With Quote
Old 04-03-2018, 10:15 AM   #14
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M465 wont go into gear

Ok. Will try and move that tonight. Will update then.

Tranny hump. To remove that, is to pull seat and flooring up, correct?
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 10:52 AM   #15
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M465 wont go into gear

Quote:
Originally Posted by ratman90 View Post

Tranny hump. To remove that, is to pull seat and flooring up, correct?
Affeared so!
Couple qs first.

Can you push the truck at all or does it not move at all?
What gear was it in when it had the original problem?
geezer#99 is offline   Reply With Quote
Old 04-03-2018, 11:16 AM   #16
Peanutbutter
Account Suspended
 
Join Date: Feb 2013
Location: Mesa, Colorado
Posts: 450
Re: 1972 C10 2wd M20 wont go into gear

I don't quite understand, does it go into gear with the engine off. Pull the inspection cover under the flywheel with the 4 bolts, have someone step on the clutch while you're under neath the flywheel and see if the clutch is loose from the flywheel. Sometimes the disc will rust to the flywheel, with the clutch pedal down stick a screwdriver between the disc and the flywheel. I've had this happen twice now and only takes couple minutes to fix.
Peanutbutter is offline   Reply With Quote
Old 04-03-2018, 11:24 AM   #17
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

Yes it will move. Seems to be stuck in neutral.

Was going from 2 to 3 or 3 to 4. Not 100% sure.

Could not get into gear, so he eventually settled on neutral and coasted into a parking lot.

Not sure if i could get inspection cover off because of that crossmember. Once i get all the dirt uncaked and cleaned off, youre saying that i should be able to remove that insp. Cover?
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 11:37 AM   #18
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 9,730
Re: 1972 C10 2wd M20 wont go into gear

I suspect you think the cover near the crossmember is an inspection cover.
It’s not. It’s a cover for a pto if you need one.
You won’t see anything in there to help.
You might need to pull the top off the tranny.
geezer#99 is offline   Reply With Quote
Old 04-03-2018, 11:48 AM   #19
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

I was going off what peanutbutter had said about the flywheel inspection cover.

So, short of checking down shifter hole itself to see if all is lined up and well there, i need to pull the seat, hopefully unbolt the hump. Then unbolt tranny from engine and slide back to remove.

Sound correct? How heavy is this beast? Tranny jack needed?
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 11:56 AM   #20
Peanutbutter
Account Suspended
 
Join Date: Feb 2013
Location: Mesa, Colorado
Posts: 450
Re: 1972 C10 2wd M20 wont go into gear

Pulling trans should be last resort, 465 is very heavy, do not try to pull without trans jack. Was this trans working when parked?
Peanutbutter is offline   Reply With Quote
Old 04-03-2018, 12:02 PM   #21
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

Trans has been working almost daily since we pulled it out of a field last july. Did not check fluid level in it though. Has not given any problems until it stopped working while going down the road.

Has 90k miles on it
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 12:12 PM   #22
Peanutbutter
Account Suspended
 
Join Date: Feb 2013
Location: Mesa, Colorado
Posts: 450
Re: 1972 C10 2wd M20 wont go into gear

I went back and read post #4 again, if this started with the other guy it still sounds like clutch is not releasing, tin flywheel cover will come off but is tight, donot try to remove cross member. This could be a throwout bearing issue.
Peanutbutter is offline   Reply With Quote
Old 04-03-2018, 12:21 PM   #23
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

K. Will check the shifter slot and see what i can do to get the insp cover off to see what clutch is doing, or not doing
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Old 04-03-2018, 12:24 PM   #24
Peanutbutter
Account Suspended
 
Join Date: Feb 2013
Location: Mesa, Colorado
Posts: 450
Re: 1972 C10 2wd M20 wont go into gear

OK, if its been working daily the disc is not rusted to flywheel, have someone step on clutch pedal and watch to see if clutch fork is moving back and forth in the bellhousing. I would still pull the tin cover and watch the action of the throwout bearing when you step on the clutch pedal. Are you in Colorado or other. If its throwout bearing issue you will still have to pull trans.

Last edited by Peanutbutter; 04-03-2018 at 12:31 PM.
Peanutbutter is offline   Reply With Quote
Old 04-03-2018, 12:32 PM   #25
ratman90
Registered User
 
Join Date: Jul 2017
Location: Longmont
Posts: 29
Re: 1972 C10 2wd M20 wont go into gear

Yeah. I am in Longmont. North of Denver east of the republic of Boulder.
__________________
1972 C10 LWB 2WD
307 4 speed
Rescued from Field July 2017
ratman90 is offline   Reply With Quote
Reply

Bookmarks

Tags
4speed, m20, muncie m20

Thread Tools
Display Modes

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 10:18 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Copyright 1997-2013 67-72chevytrucks.com