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 04-19-2017, 11:57 PM   #1
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
sm 465 popping out of gear

Hi, just thought I would share this, I just installed a new crate engine in my truck, then went down and registered it,,,now for it's maiden voyage with the new engine, runs great!!!! but the 4 spd was popping out of third gear, I hadnt driven the truck since I put this sm465/205 in it, except down the road at my house but never getting on it......looked online and found Anaheim Gear has replacement third gears upgraded from the old,I guess this is a common problem with sm465's never had the problem with my other trucks ...got the gear and slider, ordered a bearing /synchro kit and gasket set and there is a sleeve that replaces some lock rings on the intermediate shaft....anyway, I got it all back together and in the truck and SUCCESS!!!!!!! shifts perfect and stays in all gears like it should....I have a press and made a couple specialty tools from pieces of pipe and made my own socket to tighten the rear main shaft nut and used a bearing remover with a gear puller to remove the bearings ,it was a big job but worth it....there is a great youtube video of a guy tearing apart his sm465 from a 4 wheel drive like mine, was helpful
El Dorado Jim is offline   Reply With Quote
Old 04-20-2017, 12:55 AM   #2
'68OrangeSunshine
Senior Member
 
'68OrangeSunshine's Avatar
 
Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 3,770
Re: sm 465 popping out of gear

I have had the same problem on my SM465 in a '68 C/10 [292 L6, 3.73 posi rear.]
I keep my hand on the shift knob if it starts to happen.

Don't get that gripe on my '71 GMC Jimmy [350,SM465,NP205,3.73 posi].

Wonder what causes it?
__________________


Every 25 years I like to rebuild that 292, whether it needs it or not.
'68OrangeSunshine is online now   Reply With Quote
Old 04-20-2017, 07:45 AM   #3
palallin
Registered User
 
Join Date: Jul 2002
Location: St. James, MO
Posts: 814
Re: sm 465 popping out of gear

I have not heard of this problem before, and don't have it with mine, but I am curious as to what you find out.
__________________
'69 Longstep K-10: 327/SM465/T-221/Closed Knuckle Dana44/12-bolt.
palallin is offline   Reply With Quote
Old 04-20-2017, 11:32 AM   #4
68GRNK20
Registered User
 
68GRNK20's Avatar
 
Join Date: Feb 2017
Location: BC Canada
Posts: 30
Re: sm 465 popping out of gear

I have heard of this before, seen some info online on how to fix, glad you were able to have success. I have this transmission in my truck but seeing as I have yet to drive it there hasn't been any problems.
68GRNK20 is offline   Reply With Quote
Old 04-20-2017, 02:28 PM   #5
BILT4ME
Registered User
 
Join Date: Jul 2016
Location: Olathe, KS
Posts: 226
Re: sm 465 popping out of gear

I have had this problem on nearly every truck with a 4 speed in it. It's because the gearing is such that the truck spends most of it's life in 3rd gear. Towing, starting, stopping, etc is mostly in 3rd. Most folks only downshift from 4th to 3rd, and rarely to 2nd due to the granny low.

It has to do with bearing and gear wear and there is just enough that it allows misalignment.

I am fearing this EXACT same scenario on my son's 70 GMC K2500 that we're doing. Dropping in a crate engine to a worn transmission/transfer case.

I hope that's not the case, but if I was a betting man.........
__________________
1970 GMC K2500
Dis-use is harder on a car than mis-use.
BILT4ME is offline   Reply With Quote
Old 04-20-2017, 03:19 PM   #6
4X4GMC1972
Registered User
 
4X4GMC1972's Avatar
 
Join Date: Apr 2005
Location: Dallas, Texas
Posts: 414
Re: sm 465 popping out of gear

This is a common problem. The transmission shop I use tells me its because people usually rest their hand on the shifter and are slightly pulling on it before upshifting. Time for a rebuild.
__________________
1978 Dodge Omni
4X4GMC1972 is offline   Reply With Quote
Old 04-20-2017, 10:13 PM   #7
'68OrangeSunshine
Senior Member
 
'68OrangeSunshine's Avatar
 
Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 3,770
Re: sm 465 popping out of gear

Mine started slipping even after a rebuild.
__________________


Every 25 years I like to rebuild that 292, whether it needs it or not.
'68OrangeSunshine is online now   Reply With Quote
Old 04-21-2017, 12:00 AM   #8
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

I have not had this problem with the other sm465's in my other trucks...I probably have over 200,000 miles on the one in my 74 K20 and never a problem,,,Bilt4me, they are not hard to rebuild, just a pain in the a#s to pull and put back in....especially mine with the transfer case behind it....don't be afraid to rebuild it yourself if you have a press.....
El Dorado Jim is offline   Reply With Quote
Old 04-21-2017, 06:50 AM   #9
saxart
Senior Member
 
saxart's Avatar
 
Join Date: Aug 2012
Location: St. Croix River Valley, WI
Posts: 346
Re: sm 465 popping out of gear

Jim-
Wow, you're quick. You got that engine in and running, then pulled and redid the tranny in a heartbeat. Nice work!

I hope to get my "crate" installed this weekend. Got any tips for wrestling in the SM465 back in when the time comes?
__________________
Meet "Old Roy": http://67-72chevytrucks.com/vboard/s...d.php?t=707801
saxart is offline   Reply With Quote
Old 04-21-2017, 08:09 AM   #10
Mike C
Registered User
 
Mike C's Avatar
 
Join Date: Dec 1999
Location: Austin, TX, USA
Posts: 6,070
Re: sm 465 popping out of gear

You start typing "SM465 pops" and Google shows top searches which finishes up "out of 3rd gear". One common suggestions is:

"There are two snaprings, they retain the input countergear and the third gear countergear. They wear and allow the two to walk, which causes the transmission to jump out of gear. These are replaced with a spacer bushing (p/n 14020811 from Anaheim Gear, essentially tubing as far as I can tell) like this.

But visit the Google and you will find a dozen threads addressing this.
__________________
44 Willys MB
52 M38A1
64 Corvette Coupe
68 Camaro 'vert LT1 & TH700
69 Z/28 355 12.6's @110
72 Jimmy 4WD 4spd 4" & 35's
72 240Z-2.9l L6, triple Del'Lortos, T5, 12mm R200 LSD
85 FJ1100 & 01 XR400
86 Kawasaki X2 & 89 SX650 w/PJS cylinder and dual carbs
02 GMC 2500HD 4x4 Duramax
Mike C is offline   Reply With Quote
Old 04-21-2017, 10:56 AM   #11
BILT4ME
Registered User
 
Join Date: Jul 2016
Location: Olathe, KS
Posts: 226
Re: sm 465 popping out of gear

Quote:
Originally Posted by Mike C View Post
You start typing "SM465 pops" and Google shows top searches which finishes up "out of 3rd gear". One common suggestions is:

"There are two snaprings, they retain the input countergear and the third gear countergear. They wear and allow the two to walk, which causes the transmission to jump out of gear. These are replaced with a spacer bushing (p/n 14020811 from Anaheim Gear, essentially tubing as far as I can tell) like this.

But visit the Google and you will find a dozen threads addressing this.
Great info Mike! Thanks!

What do y'all think: We currently have the engine out of the truck. Driveshafts are off. Transmission and transfer case are still in the truck.

Should we drop the transmission and TCase NOW and go through them for seals, the 3rd gear issue, seals and bearing? We have no idea if the trans /Case leak, make noise, are worn, or anything.

Should we pull them out and go through them or finish dropping in the engine and DS, get it up and going and see how it goes from there?

The SM465 and NP205 are the only pieces of the driveline that have NOT been rebuilt at this time. Rear axle had spiders blown out and center pin welded in, front axle had totally shot front knuckles and pinion leaks. Rebuilt both.

What say Y'all?
__________________
1970 GMC K2500
Dis-use is harder on a car than mis-use.
BILT4ME is offline   Reply With Quote
Old 04-21-2017, 09:38 PM   #12
Mike C
Registered User
 
Mike C's Avatar
 
Join Date: Dec 1999
Location: Austin, TX, USA
Posts: 6,070
Re: sm 465 popping out of gear

Pay the man now or pay the man later... I would do it now. While you are still working on it and not down the road when all is finished and you want to drive.
__________________
44 Willys MB
52 M38A1
64 Corvette Coupe
68 Camaro 'vert LT1 & TH700
69 Z/28 355 12.6's @110
72 Jimmy 4WD 4spd 4" & 35's
72 240Z-2.9l L6, triple Del'Lortos, T5, 12mm R200 LSD
85 FJ1100 & 01 XR400
86 Kawasaki X2 & 89 SX650 w/PJS cylinder and dual carbs
02 GMC 2500HD 4x4 Duramax
Mike C is offline   Reply With Quote
Old 04-21-2017, 10:50 PM   #13
nds1968
Registered User
 
nds1968's Avatar
 
Join Date: Mar 2006
Location: Pittsburgh
Posts: 1,444
Re: sm 465 popping out of gear

My SM420 had the same problem, I bought some NOS parts and had it rebuilt... Not cheap.
__________________
Nate

1967 short fleet Project Blue Goose
'If it don't bounce back... heeheehee you go hungry!" Blues Brothers
nds1968 is offline   Reply With Quote
Old 04-22-2017, 12:24 AM   #14
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by Mike C View Post
You start typing "SM465 pops" and Google shows top searches which finishes up "out of 3rd gear". One common suggestions is:

"There are two snaprings, they retain the input countergear and the third gear countergear. They wear and allow the two to walk, which causes the transmission to jump out of gear. These are replaced with a spacer bushing (p/n 14020811 from Anaheim Gear, essentially tubing as far as I can tell) like this.

But visit the Google and you will find a dozen threads addressing this.
I installed the spacer also on mine, even though my snap rings were still in good shape,no instructions came with the spacer, I looked it up online, you remove the two snap rings and a spacer on the intermediate shaft and install the spacer, figured I may as well fix it right, but the third gear and slider should be replaced as well, it is an upgraded gear ,I talked to a guy at Anaheim gear and ordered the gear and spacer over the phone....was about $160.00 for the parts, he also sent replacement springs for the shift forks...but I didnt replace mine, the detents were really tight ...I ordered a bearing and synchro/gasket kit off of Amazon for about $100.00...I did the work myself and pretty cheap vs. taking it to a trans shop...

Last edited by El Dorado Jim; 04-22-2017 at 12:32 AM.
El Dorado Jim is offline   Reply With Quote
Old 04-22-2017, 12:30 AM   #15
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by saxart View Post
Jim-
Wow, you're quick. You got that engine in and running, then pulled and redid the tranny in a heartbeat. Nice work!

I hope to get my "crate" installed this weekend. Got any tips for wrestling in the SM465 back in when the time comes?
yeah buddy, it helps that I'm retired.....have time now!...pulling the trans/transcase was fairly easy, I have a transmission jack...pulled them as a unit, I installed the 465 by itself then the 205 w/adapter after that ...and ended up having my son help me align the transcase/crossmember ,just couldnt get it by myself...just wish I knew trans was bad when I had the engine out!!!let us know when you get yours running!!!my engine runs great, real happy with it..have less than 50 miles on it so far though..
El Dorado Jim is offline   Reply With Quote
Old 04-22-2017, 12:33 AM   #16
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by nds1968 View Post
My SM420 had the same problem, I bought some NOS parts and had it rebuilt... Not cheap.
my brother in law has a sm420 in his jeep, it is popping out of second gear occasionally, any ideas? bad second gear?
El Dorado Jim is offline   Reply With Quote
Old 04-22-2017, 12:41 AM   #17
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by BILT4ME View Post
Great info Mike! Thanks!

What do y'all think: We currently have the engine out of the truck. Driveshafts are off. Transmission and transfer case are still in the truck.

Should we drop the transmission and TCase NOW and go through them for seals, the 3rd gear issue, seals and bearing? We have no idea if the trans /Case leak, make noise, are worn, or anything.

Should we pull them out and go through them or finish dropping in the engine and DS, get it up and going and see how it goes from there?

The SM465 and NP205 are the only pieces of the driveline that have NOT been rebuilt at this time. Rear axle had spiders blown out and center pin welded in, front axle had totally shot front knuckles and pinion leaks. Rebuilt both.

What say Y'all?
I think I would try and run them like they are, chances are they are fine....but if you can afford it , go ahead and rebuild the trans...atleast
El Dorado Jim is offline   Reply With Quote
Old 04-22-2017, 02:37 PM   #18
nds1968
Registered User
 
nds1968's Avatar
 
Join Date: Mar 2006
Location: Pittsburgh
Posts: 1,444
Re: sm 465 popping out of gear

Quote:
Originally Posted by El Dorado Jim View Post
my brother in law has a sm420 in his jeep, it is popping out of second gear occasionally, any ideas? bad second gear?
Call this guy, he knows everything there is to know about all these transmissions. He has an add on CL but he has an actual shop packed full of parts https://pittsburgh.craigslist.org/pts/6099317167.html You can also contact Novaks https://www.novak-adapt.com/catalog/...s/sm420-parts/ but they couldn't help me, they said the parts I needed are impossible to find but that guy on CL had them but he knew what he had... Nate
__________________
Nate

1967 short fleet Project Blue Goose
'If it don't bounce back... heeheehee you go hungry!" Blues Brothers
nds1968 is offline   Reply With Quote
Old 04-22-2017, 09:56 PM   #19
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by nds1968 View Post
Call this guy, he knows everything there is to know about all these transmissions. He has an add on CL but he has an actual shop packed full of parts https://pittsburgh.craigslist.org/pts/6099317167.html You can also contact Novaks https://www.novak-adapt.com/catalog/...s/sm420-parts/ but they couldn't help me, they said the parts I needed are impossible to find but that guy on CL had them but he knew what he had... Nate
thanks a bunch!
El Dorado Jim is offline   Reply With Quote
Old 05-18-2017, 11:56 AM   #20
BILT4ME
Registered User
 
Join Date: Jul 2016
Location: Olathe, KS
Posts: 226
Re: sm 465 popping out of gear

Quote:
Originally Posted by El Dorado Jim View Post
I think I would try and run them like they are, chances are they are fine....but if you can afford it , go ahead and rebuild the trans...atleast
Well, we made the decision to pull both the transmission and transfer case and have them rebuilt.

We COULD rebuild them ourselves, but we have too many other irons in the fire right now.

What pushed us over the edge was that I was under the truck and discovered that the transfer case rear output shaft bearing case was leaking and there was no oil in the unit. Also, after looking at how blown-out the rear differential was on this truck, ALL that same wear and tear has gone through the trans and T-Case.

Since the popping out of gear thing is SOOO annoying and leaks are also annoying, we decided to do it. The engine is out, the DS are off, there is no exhaust in the way.....It will take us less than half the time to do it now as to do it later.

I dropped them as a unit last night by myself in the driveway in 2-1/2 hours and I'm slow. I didn't realize that together, they are at least 500 lb. So, that was a bit of a challenge laying on my back trying to push around something that weighs more than I do. I didn't use a transmission jack, but a floor jack and some ratchet straps across the frame, and I still have all my fingers.......

Going back in should also only be a couple hours since we can go straight up and not have to worry about the tunnel and the interior.

I'm estimating about $1100 to have the two rebuilt including labor and parts (total for both)

Also, we found a shop in Topeka, KS that does LOTS of rebuilds and customs in 4x4's and prices are reasonable.

4x4Land.com

Mike let us look around for about 2 hours one Saturday in ONE of his 4 warehouses. He has NP205's and complete axle assemblies stacked on pallets and racks covering the walls and shelves. I was very impressed. Jeeps are his bread and butter, but his personal vehicles have been the 67-72 Chevy's.
__________________
1970 GMC K2500
Dis-use is harder on a car than mis-use.
BILT4ME is offline   Reply With Quote
Old 05-18-2017, 05:07 PM   #21
mattfranklin
Senior Member
 
mattfranklin's Avatar
 
Join Date: Dec 2011
Location: Moraga, CA
Posts: 246
Re: sm 465 popping out of gear

Was this the video?
https://www.youtube.com/watch?v=0wMUZ-m4f6w
I thought it was pretty good, too.
__________________
(Very) Slow-Going Build Thread: Stock 1970 Short Step with Stock 1970 LT-1

http://67-72chevytrucks.com/vboard/s...d.php?t=567340
mattfranklin is offline   Reply With Quote
Old 05-20-2017, 02:20 AM   #22
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by BILT4ME View Post
Well, we made the decision to pull both the transmission and transfer case and have them rebuilt.

We COULD rebuild them ourselves, but we have too many other irons in the fire right now.

What pushed us over the edge was that I was under the truck and discovered that the transfer case rear output shaft bearing case was leaking and there was no oil in the unit. Also, after looking at how blown-out the rear differential was on this truck, ALL that same wear and tear has gone through the trans and T-Case.

Since the popping out of gear thing is SOOO annoying and leaks are also annoying, we decided to do it. The engine is out, the DS are off, there is no exhaust in the way.....It will take us less than half the time to do it now as to do it later.

I dropped them as a unit last night by myself in the driveway in 2-1/2 hours and I'm slow. I didn't realize that together, they are at least 500 lb. So, that was a bit of a challenge laying on my back trying to push around something that weighs more than I do. I didn't use a transmission jack, but a floor jack and some ratchet straps across the frame, and I still have all my fingers.......

Going back in should also only be a couple hours since we can go straight up and not have to worry about the tunnel and the interior.

I'm estimating about $1100 to have the two rebuilt including labor and parts (total for both)

Also, we found a shop in Topeka, KS that does LOTS of rebuilds and customs in 4x4's and prices are reasonable.

4x4Land.com

Mike let us look around for about 2 hours one Saturday in ONE of his 4 warehouses. He has NP205's and complete axle assemblies stacked on pallets and racks covering the walls and shelves. I was very impressed. Jeeps are his bread and butter, but his personal vehicles have been the 67-72 Chevy's.
good call, you will be glad you had them rebuilt,glad you could afford it , will save you alot of work if you had to pull them later... I just dont have the money to have them done at a shop...
El Dorado Jim is offline   Reply With Quote
Old 05-20-2017, 01:46 PM   #23
Klmor
Registered User
 
Join Date: May 2017
Location: Shreveport, la
Posts: 26
Re: sm 465 popping out of gear

Quote:
Originally Posted by mattfranklin View Post
Was this the video?
https://www.youtube.com/watch?v=0wMUZ-m4f6w
I thought it was pretty good, too.
Great video.
Klmor is offline   Reply With Quote
Old 05-22-2017, 12:55 AM   #24
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 1,787
Re: sm 465 popping out of gear

Quote:
Originally Posted by mattfranklin View Post
Was this the video?
https://www.youtube.com/watch?v=0wMUZ-m4f6w
I thought it was pretty good, too.
yes that is the one....
El Dorado Jim is offline   Reply With Quote
Old 05-22-2017, 01:12 PM   #25
BILT4ME
Registered User
 
Join Date: Jul 2016
Location: Olathe, KS
Posts: 226
Re: sm 465 popping out of gear

Quote:
Originally Posted by mattfranklin View Post
Was this the video?
https://www.youtube.com/watch?v=0wMUZ-m4f6w
I thought it was pretty good, too.
Thanks Matt! It was your posting of this video that reminded me what it takes to rebuild these. When I lived on the farm, I had access to the presses, torches, space, and all that.

Now that I'm a city dweller (for 22 years) I only have a 2 car garage and driveway to accomplish this task.

I rebuilt a SM465 30 years ago, but forgot how much work it was and I was in my 20's then. Not as easy now as it was then!

We will have an all-new driveline when we're done. That will help with long-term reliability.

Thanks guys!
__________________
1970 GMC K2500
Dis-use is harder on a car than mis-use.
BILT4ME is offline   Reply With Quote
Reply

Bookmarks

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 06:42 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 1997-2013 67-72chevytrucks.com