Converting manual to auto - The 1947 - Present Chevrolet & GMC Truck Message Board Network

jays68yak · 11-04-2002, 01:55 AM

Im thinking about buying a suburban with a 4 speed. I was wondering what kinda issues I will run into swicthing over. Like Iam I going to need a new driveshaft? I was thinking of using a 700r4 or a 4l60 or 4l80 if i can find one at a good price. Are any of those the same lenght as athe 4 speed? How hard would it be to put in a different column, so that I can shift for there instead of the floor? How about the pedals what would be a good donor truck to get a brake pedal from?

Alexis · 11-04-2002, 02:34 AM

700r are long then the 4 speed man. in the trucks. Your going to need to get the linkage and a bracket that hooks up to the frame, But these things are not very hard to install. Brake pedal?why would you need a new brake pedal? Oh i've seen some 700r's for about 800 bucks rebuilt

Spoof · 11-04-2002, 10:48 AM

I'm not sure about the drive shaft length but it's likely you will have to change it, also the th400 has a different spline count on the output shaft than the th350 so that should be considered.
I know you will have to swap in an auto tranny cross member, or fab one up ( fairly simple, just a length of flat steel with some holes)
Also you will need to swap your flywheel out and a flexplate in.

jays68yak · 11-04-2002, 11:24 AM

Yeah I figured about eh crossmember. I helped a friend make one from 2x3 steel. It looked really trick, I think I might do that again.

New brake pedal so that I could get rid of the clutch pedal.

kilomanjaro · 11-04-2002, 12:01 PM

Like said above i think you will need a new driveshaft, and auto tranny x-member, a auto steering column with all the linkage, you will also have to run a vaccum line from the carb to the modulator, and you will have to get the carburator bracket that holds the detent cable for the tranny. I may be able to get you everything you need. i sent you an email. or email me at kilomanjaro63@hotmail.com thanks
john

Rod · 11-04-2002, 12:13 PM

http://67-72chevytrucks.com/tech/trannyswap.html

Project1970 · 11-04-2002, 11:17 PM

Regarding tranny selection...the 700R4 is going to be your best bet. The 4L60 is actually the same, but I think they were only made for one year or so before they went to the 4L60E; I think it might be possible to convert a computer-controlled 4L60E to a normal 4L60/700R4 (just a name change between those). The 4L80E is a cool, tough tranny, but is a pain to find, extremely expensive to buy (it seems they run about double a 700R4!) and they also need the IIRC $300 or so transmission computer that B&M makes.

jays68yak · 11-04-2002, 11:47 PM

700r4 from www.700r4.com $800 plus converter
700r4 from junk yard (good used one) $550 plus $50 core with converter.
4l60 from same junk yard 700 or 800 with $100 core with converter.

Project1970 · 11-05-2002, 03:27 AM

4L60 or 4L60E?

There's a difference.

TERRYP · 11-05-2002, 03:42 AM

Any Tranny, $60, Pull-a-Part, Everett, WA

chevypete396 · 11-05-2002, 05:02 AM

Find a good doner vehical swap bolt ways and then sell the doner but rebuild the auto tranny before the swap. The rest is a peice of cake drill a few holes and swap parts. Probobly the cheepst way to do it too. If you find a doner with a bad tranny, you might even make some money on the deal.

But most importantly, sell the doner because saving donners is the easyest way to get into collecting useless Junk... Pete.

jays68yak · 11-05-2002, 10:55 AM

I know about the usless junk thing, I have the better part of a 66 tbird in my parents backyard. Hopefully Ill sell most or all of it this weekend at the car show. Anyone looking for a 9 inch?

jays68yak · 11-05-2002, 04:51 PM

Ok next question, would a one piece driveshaft from a 73-88 suburban fit if I convert to the 700r4? Would it bolt in and save me money having one made? I would kinda like to get the two piece out of there cuz one day the suburban will be bagged and I dont want to worry about the driveshaft. I understand that I might have to do some cutting to get the driveshaft to fit in the crossmember.

11-04-2002, 01:55 AM	#1
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	Converting manual to auto Im thinking about buying a suburban with a 4 speed. I was wondering what kinda issues I will run into swicthing over. Like Iam I going to need a new driveshaft? I was thinking of using a 700r4 or a 4l60 or 4l80 if i can find one at a good price. Are any of those the same lenght as athe 4 speed? How hard would it be to put in a different column, so that I can shift for there instead of the floor? How about the pedals what would be a good donor truck to get a brake pedal from? __________________ 1969 Chevy Project SWB Fleet, 20s, 5.3, t56, in the weeds. 1970 Chevy Truck cab on a 1979 Jimmy frame-8.1 liter 496 bbc/sm465/np203-jeds doubler-np205/d60/14bff Welded/42 tsls on recentered H1s 1998 Chevy Crew Cab K3500 SAS'd with hpd60, links and swayaway coilovers. 8.1l vortec DD/towrig "I like long walks, especially when they are taken by people who annoy me. "

11-04-2002, 10:48 AM	#3
Spoof Registered User Join Date: Jul 2000 Location: Victoria,BC, Canada Posts: 1,300	I'm not sure about the drive shaft length but it's likely you will have to change it, also the th400 has a different spline count on the output shaft than the th350 so that should be considered. I know you will have to swap in an auto tranny cross member, or fab one up ( fairly simple, just a length of flat steel with some holes) Also you will need to swap your flywheel out and a flexplate in. __________________ 71 GMC 1500 LWB Last edited by Spoof; 11-04-2002 at 10:51 AM.

11-04-2002, 11:24 AM	#4
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	Yeah I figured about eh crossmember. I helped a friend make one from 2x3 steel. It looked really trick, I think I might do that again. New brake pedal so that I could get rid of the clutch pedal. __________________ 1969 Chevy Project SWB Fleet, 20s, 5.3, t56, in the weeds. 1970 Chevy Truck cab on a 1979 Jimmy frame-8.1 liter 496 bbc/sm465/np203-jeds doubler-np205/d60/14bff Welded/42 tsls on recentered H1s 1998 Chevy Crew Cab K3500 SAS'd with hpd60, links and swayaway coilovers. 8.1l vortec DD/towrig "I like long walks, especially when they are taken by people who annoy me. "

11-04-2002, 12:01 PM	#5
kilomanjaro Senior Member Join Date: Mar 2001 Location: From Kansas now in Palmer, Alaska Posts: 807	tranny swap Like said above i think you will need a new driveshaft, and auto tranny x-member, a auto steering column with all the linkage, you will also have to run a vaccum line from the carb to the modulator, and you will have to get the carburator bracket that holds the detent cable for the tranny. I may be able to get you everything you need. i sent you an email. or email me at kilomanjaro63@hotmail.com thanks john

11-04-2002, 12:13 PM	#6
Rod Join Date: Dec 1999 Location: Eastern - Manitoba Canada, Winnipeg Posts: 4,369	http://67-72chevytrucks.com/tech/trannyswap.html __________________ Senior active founding member. 70 3/4 ton GMC Suburban 4x4 250/4 spd. 71 1/2 ton Suburban Chevy 4x4, 350/350 72 Chev 1 ton tow truck 402BB w/Holmes 440 wrecker on propane 2005 FLSTSCI Harley Springer 85 FXSB Harley Lowrider 72 Triumph 650 Bonneville 5spd "Poor people don't have hobbies" Quote from wife.

11-04-2002, 02:34 AM	#2
Alexis Member since 2000 Join Date: Dec 2000 Location: Mountain View Ca / Mexico Posts: 7,879	700r are long then the 4 speed man. in the trucks. Your going to need to get the linkage and a bracket that hooks up to the frame, But these things are not very hard to install. Brake pedal?why would you need a new brake pedal? Oh i've seen some 700r's for about 800 bucks rebuilt

11-04-2002, 11:17 PM	#7
Project1970 14.1 @ 96MPH Join Date: Jul 2001 Location: Mesa, AZ Posts: 2,811	Regarding tranny selection...the 700R4 is going to be your best bet. The 4L60 is actually the same, but I think they were only made for one year or so before they went to the 4L60E; I think it might be possible to convert a computer-controlled 4L60E to a normal 4L60/700R4 (just a name change between those). The 4L80E is a cool, tough tranny, but is a pain to find, extremely expensive to buy (it seems they run about double a 700R4!) and they also need the IIRC $300 or so transmission computer that B&M makes. __________________ Project1970 - LS1 Swap Complete!

11-04-2002, 11:47 PM	#8
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	700r4 from www.700r4.com $800 plus converter 700r4 from junk yard (good used one) $550 plus $50 core with converter. 4l60 from same junk yard 700 or 800 with $100 core with converter. __________________ 1969 Chevy Project SWB Fleet, 20s, 5.3, t56, in the weeds. 1970 Chevy Truck cab on a 1979 Jimmy frame-8.1 liter 496 bbc/sm465/np203-jeds doubler-np205/d60/14bff Welded/42 tsls on recentered H1s 1998 Chevy Crew Cab K3500 SAS'd with hpd60, links and swayaway coilovers. 8.1l vortec DD/towrig "I like long walks, especially when they are taken by people who annoy me. "

11-05-2002, 03:27 AM	#9
Project1970 14.1 @ 96MPH Join Date: Jul 2001 Location: Mesa, AZ Posts: 2,811	4L60 or 4L60E? There's a difference. __________________ Project1970 - LS1 Swap Complete!

11-05-2002, 03:42 AM	#10
TERRYP GYRO GEARLOOSE Join Date: Jun 2000 Location: Nevada City, CAEverett, WA Posts: 361	Any Tranny, $60, Pull-a-Part, Everett, WA __________________ Nevada City, CA Everett, Washington 57 3/4 rat, 235, 3spd 66 C-10 Panel, SWB. 350 from '68, 200R4 tranny, 3.07 rear ratio, restoring 68 C10 LWB 350 4spd, 4.56 rear dump runner 82 Camaro, 305, THM-200-R4 84 Monte Carlo 305 TH350, land tuna 85 Tercel SW, snow runner DISGRACED OUTLAW MEMBER OF THE DRUM BRAKE CLUB

11-05-2002, 05:02 AM	#11
chevypete396 Registered User Join Date: Mar 2002 Location: Fernley, Nevada, USA Posts: 540	How I would do it... Find a good doner vehical swap bolt ways and then sell the doner but rebuild the auto tranny before the swap. The rest is a peice of cake drill a few holes and swap parts. Probobly the cheepst way to do it too. If you find a doner with a bad tranny, you might even make some money on the deal. But most importantly, sell the doner because saving donners is the easyest way to get into collecting useless Junk... Pete. __________________ 1968 Chevy - 3/4 Ton - 4X4 - Longbed - 383ci - TH350 - NP205 Building the motor, painting the engine bay, rewireing everything... (775)-527-1199 / ryanspeterson@msn.com

11-05-2002, 10:55 AM	#12
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	I know about the usless junk thing, I have the better part of a 66 tbird in my parents backyard. Hopefully Ill sell most or all of it this weekend at the car show. Anyone looking for a 9 inch? __________________ 1969 Chevy Project SWB Fleet, 20s, 5.3, t56, in the weeds. 1970 Chevy Truck cab on a 1979 Jimmy frame-8.1 liter 496 bbc/sm465/np203-jeds doubler-np205/d60/14bff Welded/42 tsls on recentered H1s 1998 Chevy Crew Cab K3500 SAS'd with hpd60, links and swayaway coilovers. 8.1l vortec DD/towrig "I like long walks, especially when they are taken by people who annoy me. "

11-05-2002, 04:51 PM	#13
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	Ok next question, would a one piece driveshaft from a 73-88 suburban fit if I convert to the 700r4? Would it bolt in and save me money having one made? I would kinda like to get the two piece out of there cuz one day the suburban will be bagged and I dont want to worry about the driveshaft. I understand that I might have to do some cutting to get the driveshaft to fit in the crossmember. __________________ 1969 Chevy Project SWB Fleet, 20s, 5.3, t56, in the weeds. 1970 Chevy Truck cab on a 1979 Jimmy frame-8.1 liter 496 bbc/sm465/np203-jeds doubler-np205/d60/14bff Welded/42 tsls on recentered H1s 1998 Chevy Crew Cab K3500 SAS'd with hpd60, links and swayaway coilovers. 8.1l vortec DD/towrig "I like long walks, especially when they are taken by people who annoy me. "



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