73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: hotrod24 on October 28, 2011, 11:50:13 am

Title: auto to 3 speed swap..
Post by: hotrod24 on October 28, 2011, 11:50:13 am
Ok i have a 1980 c10 with a low hump and i am going to swap back to a manual 3 speed because thats what the truck was before i think lol, It looks like it has a brake pedal from a clutch set up so thats what made me think it used to be 3 speed and someone just took the clutch out but it does not have the bracket on the frame for the bell crank and i cannot find the clutch rod hole going to the bell crank, What would be the best way of finding out if it used to be a 3 speed?

Thanks

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1348.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1349.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1350-Copy.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1351.jpg)
Title: Re: auto to 3 speed swap..
Post by: 1980c10 on October 28, 2011, 02:16:13 pm
I think your answer is in your question. Most likely with no signs of linkage pieces, It probably was an A/T. Its unlikely that someone would have caught every piece. Look for signs of rivets for the frame bracket(cutting or grinding marks). do you have an auto dash? look for a properly installed neutral saftey switch as if this was changed the wires may have connecters just before the plug.  my 1980 c10 had the sm465 and had a removable cover on the floor hump.
(http://i686.photobucket.com/albums/vv222/titera1/0423111137.jpg)
forgive the modications but you get the idea.

Anyway, that does look like a clutch-brake pedal as I believe it would have been larger if an auto.
The purple and yellow wires hanging below your steering column would have originially gone to the neutral saftey switch for a clutch. Look to see if the are connected to one another.

The pedal assembly on the right would have been correct in your truck
(http://i686.photobucket.com/albums/vv222/titera1/5226953763_273919943d_b.jpg)
I don't know what the auto pedal assembly looks like but the manual version has both the clutch and brake pedal hanging from the same bracket so look for where the clutch pedal would have hung from that
Title: Re: auto to 3 speed swap..
Post by: zieg85 on October 28, 2011, 03:32:26 pm
Look for a hole in the firewall which the clutch rod would have gone through.  If it is not there your truck was most likely never a standard shift truck.  I have seen that small brake pedal on automatic trucks on some of the base model trucks.  My $.02
Title: Re: auto to 3 speed swap..
Post by: Captkaos on October 28, 2011, 03:48:23 pm
Based on the pictures of your floorpan that cab never had a manual in it.  The hole that Zieg is talking about is missing.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on October 28, 2011, 09:56:39 pm
Thanks guys, I am wanting to switch it to a 3 speed on the column so there would not be any reason to have a floor shift hole, But like chris said it has a low hump but i have heard of guys saying that they had a manual with the low hump. The brake housing set up looks nothing like the clutch set up. If it was never a manaul it will be one lol, I will keep looking for signs tho...

Also i will get some pics of the bracket linkage, The bracket is bolted not rivted so thats one other thing that made me think it was a manual...
Title: Re: auto to 3 speed swap..
Post by: 1980c10 on October 28, 2011, 10:29:02 pm
Given the condition of your floors and your goals it may not be a bad idea to find an entire cab or parts truck for that matter with a m/t. Are you looking to go with a column shifter only?
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on October 28, 2011, 10:38:10 pm
lol Yea i plan to get a welder and repair my floors or swap cabs. Its taking me a bit to get the cash up, But yea i am going with the column shifter for now...
Title: Re: auto to 3 speed swap..
Post by: zieg85 on October 28, 2011, 10:49:23 pm
FYI, the 3 speed column shift was one of GM's weak links IMO during the 73-87 era.  They seemed to wear out or completely brake, parts are next to impossible to find, or I just have had zero luck in finding any good ones in my area.  I gave up looking trying to convert my 86 C10 back to original, couldn't find a good column or the linkage needed.  Best of luck in your search...
Title: Re: auto to 3 speed swap..
Post by: HAULIN IT on October 28, 2011, 10:58:52 pm
Also i will get some pics of the bracket linkage, The bracket is bolted not rivted so thats one other thing that made me think it was a manual...
Which "bracket" are you referring to?
 As mentioned, the 2nd picture you posted would have a hole (or patched area) near the dimmer switch where the clutch rod goes down through the floor to the pivot on the frame.
I also have seen quite a few "low option" trucks with an auto trans. & the small brake pedal. The Yellow color also makes me think of "Fleet, D.O.T. , ect. which goes along with the low option truck. Is it a non-power brake set-up by chance?
If the option label is in the glovebox by some odd chance, it will tell you what trans., ect. the truck came with...assuming the cab, VIN. ect. match the decal.
Unfortunately, looking at that cab...you have much needed work than changing the trans, column, ect.
Lorne
Title: Re: auto to 3 speed swap..
Post by: Captkaos on October 29, 2011, 01:45:29 am
Also i will get some pics of the bracket linkage, The bracket is bolted not rivted so thats one other thing that made me think it was a manual...

Auto brackets were held on with bolts.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on October 29, 2011, 01:05:01 pm
Yea some of the 3 speed coulmns are messed up but i guess you just got to find the right one.  My dad had a 67 c10 with a three on the tree and it work great.  I have alot of junk yards around me plus my i have a close relative with one that has about everything so i think i am good there and thanks for the good luck zieg85 ;) The bracket that i am talking about Lorne is the one that the linkage goes to from the tranny to the lower side of the frame right beside the tranny, I will look beside the dimmer switch and see, That area has rust holes so that might be where the hole was lol and yea it does have manual brakes and i thought the same thing about it being a state truck.  The only sticker that it has on the glove box is the camper information I know i am in need of working on other things at the this time but i am kind of just planning what will come i am getting a front clip and changing integrated head to non and looking to see if i can find a solid cab then changing the tranny i am just trying to figure out where i am at and chris yea the bracket is bolted like you said this bracket is the same one that my shop manual shows for the 3 speed confusing i know lol...

Thanks
Dusty

Title: Re: auto to 3 speed swap..
Post by: Captkaos on October 29, 2011, 05:15:07 pm
The manual tab  on the ones I have worked on were always riveted on.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on October 29, 2011, 06:45:55 pm
Yep my 78 had the bracket that the bell crank goes to and it was riveted and it shows it rivted in my shop manual to, Now the bracket that we was talking about earlier is bolted. Thats what my auto linkage goes to...
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 01, 2011, 06:01:30 pm
OK i found some holes, I think they are for the bell crank bracket but they might be to far apart? Also here is the bracket that i was talking about that the 3 speed tranny used that my auto lever is going to... 

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1357.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1367.jpg)

Could i use this bracket with my 3 speed manual?
(http://i222.photobucket.com/albums/dd224/74chevy/SANY1365.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/SANY1360.jpg)
Title: Re: auto to 3 speed swap..
Post by: 1979C20 on November 01, 2011, 07:55:29 pm
Unless they replaced the cab, there would be holes for the clutch rod and the shifter. check your rpo codes to see what tranny it had.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 02, 2011, 10:46:49 am
Ok i found it!  My 78 I had tore down, I found a picture of the frame and the bracket.  It is the same bolt pattern as my 80 two wheel drive.  So I guess I am good there. Yea I cannot find the holes for the clutch rod.  I cannot find an RPO codes either. 

(http://i222.photobucket.com/albums/dd224/74chevy/SANY0496-1.jpg)
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 02, 2011, 11:46:07 am
The Auto setup is mounted below the frame with Rivets, the manual setup is mounted above the frame and much further forward than where the auto setup is.  You cannot use one for the other...

This is the clutch bracket:
(http://captkaoscustoms.com/images/clutchbrkt.jpg)
Title: Re: auto to 3 speed swap..
Post by: roger97338 on November 03, 2011, 01:52:15 pm
My 1975 (2wd) was originally a three-on-the-tree, and it has the low hump in the cab.
Title: Re: auto to 3 speed swap..
Post by: HAULIN IT on November 04, 2011, 09:25:31 pm
Ok i found it!  My 78 I had tore down, I found a picture of the frame and the bracket.  It is the same bolt pattern as my 80 two wheel drive.  So I guess I am good there. Yea I cannot find the holes for the clutch rod.  I cannot find an RPO codes either. 

(http://i222.photobucket.com/albums/dd224/74chevy/SANY0496-1.jpg)
Why would this frame have both the clutch z bar bracket & the auto bracket? Both sure appear to be factory rivets.
Hotrod, Tell us about that truck...I see it's a 4x4, but what about other details? Lorne
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 04, 2011, 10:01:39 pm
The auto bracket looks like bolts to me.  My 1973 (pictured) had the holes for the auto bracket.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 07, 2011, 03:07:23 pm
I think the 78 i had was a straight drive at one time, So thats why it has both brackets. The auto bracket was bolted but the z bar was riveted to the frame...
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 08, 2011, 01:31:44 pm
Ok i found out that my 80 2wd has always been an auto, I found an emission sticker on the core support that said it was.  So that is taken care of.  I just have to find out now how I am going to do this 3 speed swap, like where does the clutch rod come though the firewall.  Would anyone have pics of the hole in the firewall?
Title: Re: auto to 3 speed swap..
Post by: 1979C20 on November 08, 2011, 02:04:07 pm
What do you mean by "3 speed"? Do you mean three on the tree, or do you mean the sm465 4 speed with granny low?
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 08, 2011, 02:16:19 pm
Three on the tree...
Title: Re: auto to 3 speed swap..
Post by: 1979C20 on November 08, 2011, 02:18:42 pm
Okay, so you dont need to worry about a high hump or cutting a hole in the floor. I can take some pictures of my clutch rod location, but I dont know if the clut h rod is in the same place on the 3 on the tree as the SM465.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 08, 2011, 02:22:14 pm
Thanks man, They should be in the same place...
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 08, 2011, 03:03:32 pm
I am a little confused on what we are still discussing or looking for....

There are only 2 brackets.locations for pickups.  Manual and Auto.  You have both.  Manuals are the same bracket regardless of what is in the truck..  The Auto's are the same for Auto's but I vaguely think the 700R4 has a different version...  I still need to check that though..

If you are using a 3 on the tree muncie, you use the manual bracket...
Title: Re: auto to 3 speed swap..
Post by: 1979C20 on November 08, 2011, 03:24:17 pm
He is wanting to know where the clutch rod goes through the floor. I should have some pics of it for you tonight.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 08, 2011, 03:36:21 pm
Thanks...

He is wanting to know where the clutch rod goes through the floor. I should have some pics of it for you tonight.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 08, 2011, 03:53:14 pm
Yea chris i will be using the manual bracket, But as far as i know i will have to use the auto bracket to. Because of the column linkage...

(http://i222.photobucket.com/albums/dd224/74chevy/lincage206.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/lincage201.jpg)

(http://i222.photobucket.com/albums/dd224/74chevy/lincage204-1.jpg)


I am a little confused on what we are still discussing or looking for....

There are only 2 brackets.locations for pickups.  Manual and Auto.  You have both.  Manuals are the same bracket regardless of what is in the truck..  The Auto's are the same for Auto's but I vaguely think the 700R4 has a different version...  I still need to check that though..

If you are using a 3 on the tree muncie, you use the manual bracket...
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 08, 2011, 04:21:20 pm
AHH, I am on the same page now...  for the 3 on the tree linkage, yes you need that under frame bracket.
Title: Re: auto to 3 speed swap..
Post by: HAULIN IT on November 08, 2011, 11:58:39 pm
where does the clutch rod come though the firewall.  Would anyone have pics of the hole in the firewall?
I took this the other day to try to help you. The hole does not go through the firewall, it's in the toe board area of the floor. The tin patch in the picture is held on with the Two screws (can only see one in the photo) that originally held the rubber boot in place. It is pretty much straight down from the steering column...In my mind it was farther over to the Left, but it's been 15 or so since I put that patch there.
 I would start by getting the pedal assy. & Z-bar in there. Where the hole goes shouldn't be hard to figure from there but I can measure it for you if you need/want me to.
So did we decide that the 3 on the tree does use the "auto" bracket for the reverse lock-out rotate the column deal? Lorne
(http://i163.photobucket.com/albums/t285/HAULINIT/truckclutchhole001-1.jpg)
 
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 09, 2011, 03:57:34 pm
Yea sorry chris I should have been more specific on the this.  That is very good to know that I will have to have both brackets. Lorne thanks very much for taking the pic, I have looked everywhere to try and find where that rod was located in the floor my floor is so rusty that I can not see if it even has any dimples from the factory.  I will probably start with getting the pedal assembly and z bar, depends if the junk yard I go to has the set up and when I am ready I might get you to do a little measuring for me so I know the right spot.  We solved the column issue, I will need both brackets  ;)...
 
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 09, 2011, 05:15:16 pm
I got to thinking last night about this and what I posted that I thought was correct wasn't.  There isn't any frame brackets other than the Z bar that are required for a 3 on the column.  It just has 2 long bent bars running straight to the trans.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 09, 2011, 05:43:26 pm
So you are saying that i dont need both brackets?


I got to thinking last night about this and what I posted that I thought was correct wasn't.  There isn't any frame brackets other than the Z bar that are required for a 3 on the column.  It just has 2 long bent bars running straight to the trans.
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 09, 2011, 09:20:56 pm
Nope, just the Z bar.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 10, 2011, 04:00:08 pm
Ok I got to looking in my 78 shop manual last night and found this, It shows that the 4wds came with two levers which does not use the auto bracket like you said but it also shows that the 2wd does use the auto bracket,  The pics that i posted before are of a 76 2wd 3 speed linkage which does use the auto bracket.  For some odd reason GM made them like that, it does not make no sense why they would be different unless it has somehing to do with the 4wd... lol

(http://i222.photobucket.com/albums/dd224/74chevy/100_3750_00-1.jpg)
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 10, 2011, 04:06:47 pm
My 1973 that had 3 on the tree and when I converted it to a 4 speed floor shift it didn't have them.
The front bracket on the C-10 model is what the auto bracket looks like.
Title: Re: auto to 3 speed swap..
Post by: hotrod24 on November 11, 2011, 10:48:02 am
Yea the tranny linkage brackets do look the same, Did yours just have the two arms like the k-10 model?

My 80 c10 with auto...
(http://i222.photobucket.com/albums/dd224/74chevy/SANY1368.jpg)

The 76 c10 with 3 speed manual...
(http://i222.photobucket.com/albums/dd224/74chevy/lincage202-1.jpg)
Title: Re: auto to 3 speed swap..
Post by: Captkaos on November 11, 2011, 11:51:14 am
Yes, they had 2 long arms which have been LONG gone by now...