700R4 swap tip. (speedo solution) - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Longhorn Man · 02-09-2003, 06:35 PM

Call up your chevy dealer and ask for P/n 8673406. Have about 200 bucks ready too, but this tail extention housing accepts a mechanical speedo, and also has the tranny mount located in the same place as a TH400 and the 200 4R too.
Just found this in a back dated Car Craft mag.
If you feel lucky, try scrounging under the mid '80's full size GM passenger cars...but good luck on that.

spinning wheels · 02-09-2003, 06:44 PM

Longhorn, so if I install a 700r, would an Auto Meter electronic speeder work? Or what kind of speedo are people hooking up? I really didn't think about this problem until you posted. Thanks for any info.

Longhorn Man · 02-09-2003, 06:47 PM

I honestly don't know what ppl are doing. The stock 700R4 sends a signal to the computer...and no one is installing the computer in these trucks, so i have no idea what they are doing.
As for the speedo you mentioned...I don't know if that accepts the signal from the tranny directly, or if it needs a computer signal....no idea.
I've never messed with these trannys, I just read the problems y'all have, and come across solutions some times.

Dean23 · 02-09-2003, 06:59 PM

I dont think that it sends a signal to the puter those transmissions just use a relucter wheel and a power supply i believe. But I have been wrong before

Solver · 02-09-2003, 07:11 PM

Longhorn they didn't by chance show a picture of that housing? I like to scrounge and would like to know how to identify what I am looking for when I crawl under those cars. this would make the 700 almost a bolt in (if you have 400 tranny) other than wiring and drive shaft. Do you think the speedo cable on ours would reach also or would that have to be changed? I have held off on the 700 as there always seemed to be to much to mess with. Now if we could just find a model with the right driveshaft we'd be half way home. Think I'll talk to my chevy guy a see if he can pinpoint just what years and model.Thanks for the info

Bill72BB · 02-09-2003, 08:09 PM

Andy : thanks I.ve inquired about a 700r4 at several local shops no one has indicated there would be a problem with the speedo.

jays68yak · 02-09-2003, 11:00 PM

Just installed a 700r4 from a 89 camaro into my suburban. It has will use the stock cable, you might need to get a long one tho. There is more then just changing the tail housing to go from the ones that do have the electrical speedo. They also need the gear on the output shaft.
I would say install one today, just make sure to get it rebuilt first. It is a bit of work, but as in my case i went from a 4 speed to the 700r4.

Slammed67 · 02-09-2003, 11:10 PM

Mine has the mechanical speedo drive also, and I think it's a '93 trans. All I had to do was install the correct gears to make up for my rear end gears and tires size. Contact Steve at:

Bowtie Overdrives

He'd be very helpful regarding the 700R4 tranny.

Longhorn Man · 02-09-2003, 11:44 PM

I can ry to sca the pic...but it sounds like some of these guys are scoring with the camaro deal...just remember teh Camaro tranny is mounted at a slight angle...or was that just the 5 speed?

Project1970 · 02-10-2003, 12:46 AM

The 5-speed was mounted at an angle, I highly doubt the 700R4 was.

Mechanical speedo gears are no problem; all you do is remove the reluctor and "drive gear", and install a new drive gear and driven gear, along with the gear sleeve. I believe all late-model output shafts have the holes for both; the earlier ones probably just have the one for mechanical. My transmission doesn't have a year (bought from a rebuilder) but it was originally in a computer-controlled vehicle and was originally equipped with an electronic speedo.

Longhorn Man · 02-10-2003, 12:53 AM

OK, I had heard this was a big deal.
This will place the mount in the TH400 position...but with a $200 price tag, I think I would rather move my cross member. (that is IF I were to ever use one of those trannys)

Project1970 · 02-10-2003, 01:04 AM

Definitely...moving a crossmember is a lot easier than finding $200.

cdowns · 02-10-2003, 01:33 AM

well i just went with the 2004r much easier dont cut the drive shaft just screw in the tranny cable good to go and rated for more hp has better gearing WHY DO A 700R4??????

Longhorn Man · 02-10-2003, 01:36 AM

the 200 is not stronger in stock form...but a better tranny IMO.

smokekiki · 02-10-2003, 10:22 AM

It is only a couple years of 200's that are stronger.Mostly the ones from the grand nationals.I have a 700r behind a 450hp small block with no problem.Has close to 18000 miles on it.

02-09-2003, 06:35 PM	#1
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	700R4 swap tip. (speedo solution) Call up your chevy dealer and ask for P/n 8673406. Have about 200 bucks ready too, but this tail extention housing accepts a mechanical speedo, and also has the tranny mount located in the same place as a TH400 and the 200 4R too. Just found this in a back dated Car Craft mag. If you feel lucky, try scrounging under the mid '80's full size GM passenger cars...but good luck on that.

02-09-2003, 06:44 PM	#2
spinning wheels Registered User Join Date: Sep 2001 Location: Hacienda Heights, California USA Posts: 474	Longhorn, so if I install a 700r, would an Auto Meter electronic speeder work? Or what kind of speedo are people hooking up? I really didn't think about this problem until you posted. Thanks for any info. __________________ '72 GMC custom camper 350/350

02-09-2003, 06:59 PM	#4
Dean23 68cst_ss490 Join Date: May 2001 Location: edmonton,canada Posts: 1,363	I dont think that it sends a signal to the puter those transmissions just use a relucter wheel and a power supply i believe. But I have been wrong before __________________ Dean edmonton,canada a winter wonderland 2005 Chevrolet Avalanche LT cold air intake, performance exhaust, Comp cams cam, jba shorty ceramic headers. http://www.cardomain.com/ride/3090973

02-09-2003, 07:11 PM	#5
Solver Registered User Join Date: May 2000 Location: Storm Lake, Ia Posts: 1,449	Longhorn they didn't by chance show a picture of that housing? I like to scrounge and would like to know how to identify what I am looking for when I crawl under those cars. this would make the 700 almost a bolt in (if you have 400 tranny) other than wiring and drive shaft. Do you think the speedo cable on ours would reach also or would that have to be changed? I have held off on the 700 as there always seemed to be to much to mess with. Now if we could just find a model with the right driveshaft we'd be half way home. Think I'll talk to my chevy guy a see if he can pinpoint just what years and model.Thanks for the info __________________ 1972 Cheyenne Super 20 LWB-Blue 1972 Cheyenne Super 10 LWB-Black 1972 Cheyenne Super 10 LWB-Red 1972 Cheyenne Super 10 LWB-green 1972 GMC 4x4 LWB-White 1971 Cheyenne 10 LWB-Ochre 1971 Cheyenne 20 Longhorn-Copper 1971 Cheyenne 20 Longhorn-Black 1969 Custom 10 LWB-lt blue 1968 GMC 3/4 ton-green 1968 1/2 ton swb stepside-silver 1967 Chevrolet CST 10 LWB-green 1967 Chevrolet custom 20 LWB-Maroon

02-09-2003, 08:09 PM	#6
Bill72BB Thats the Hillbilly way Join Date: Jul 2001 Location: Torrance,Ca Posts: 5,979	Andy : thanks I.ve inquired about a 700r4 at several local shops no one has indicated there would be a problem with the speedo. __________________ BILL Torrance Calif 90504 Member DUF Club Member Old Farts Club 72 3/4ton Custom Camper BB402/400 trans Dynomax Cerama-coat headers , Hei distributor ,Edelbrock 1411 air,ps,pb,leafsprings ,98 chevy 60/40 seat,S10 shoulder belts tilt,3.54 Dana 60 rear. 16" Eagle wheels with LT265/75 16 tires,Gaylord Lid,H4 headlights with 100W relay conversion. " If I knew I was going to live this long I would have taken better care of myself " Marriage changes passion...suddenly you're in bed with a relative. A GUY'S PRAYER.... Lord, I pray for a nympho with huge boobs who owns a liquor store and likes to fish and hunt and has a Harley .Amen ,

02-09-2003, 06:47 PM	#3
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	I honestly don't know what ppl are doing. The stock 700R4 sends a signal to the computer...and no one is installing the computer in these trucks, so i have no idea what they are doing. As for the speedo you mentioned...I don't know if that accepts the signal from the tranny directly, or if it needs a computer signal....no idea. I've never messed with these trannys, I just read the problems y'all have, and come across solutions some times.

02-09-2003, 11:00 PM	#7
jays68yak Registered User Join Date: Oct 2002 Location: Gilroy, CA Posts: 1,454	Just installed a 700r4 from a 89 camaro into my suburban. It has will use the stock cable, you might need to get a long one tho. There is more then just changing the tail housing to go from the ones that do have the electrical speedo. They also need the gear on the output shaft. I would say install one today, just make sure to get it rebuilt first. It is a bit of work, but as in my case i went from a 4 speed to the 700r4. __________________ 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. "

02-09-2003, 11:10 PM	#8
Slammed67 Progress = 0% Join Date: Nov 2001 Location: Kansas City, MO Posts: 2,108	Mine has the mechanical speedo drive also, and I think it's a '93 trans. All I had to do was install the correct gears to make up for my rear end gears and tires size. Contact Steve at: Bowtie Overdrives He'd be very helpful regarding the 700R4 tranny. __________________ Jason - '67 GMC swb \| '57 Bel-Air 4dr hardtop \| '56 210 4dr Wagon \| 2000 GMC Sierra

02-09-2003, 11:44 PM	#9
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	I can ry to sca the pic...but it sounds like some of these guys are scoring with the camaro deal...just remember teh Camaro tranny is mounted at a slight angle...or was that just the 5 speed?

02-10-2003, 12:46 AM	#10
Project1970 14.1 @ 96MPH Join Date: Jul 2001 Location: Mesa, AZ Posts: 2,811	The 5-speed was mounted at an angle, I highly doubt the 700R4 was. Mechanical speedo gears are no problem; all you do is remove the reluctor and "drive gear", and install a new drive gear and driven gear, along with the gear sleeve. I believe all late-model output shafts have the holes for both; the earlier ones probably just have the one for mechanical. My transmission doesn't have a year (bought from a rebuilder) but it was originally in a computer-controlled vehicle and was originally equipped with an electronic speedo. __________________ Project1970 - LS1 Swap Complete!

02-10-2003, 12:53 AM	#11
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	OK, I had heard this was a big deal. This will place the mount in the TH400 position...but with a $200 price tag, I think I would rather move my cross member. (that is IF I were to ever use one of those trannys)

02-10-2003, 01:04 AM	#12
Project1970 14.1 @ 96MPH Join Date: Jul 2001 Location: Mesa, AZ Posts: 2,811	Definitely...moving a crossmember is a lot easier than finding $200. __________________ Project1970 - LS1 Swap Complete!

02-10-2003, 01:33 AM	#13
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	well i just went with the 2004r much easier dont cut the drive shaft just screw in the tranny cable good to go and rated for more hp has better gearing WHY DO A 700R4?????? __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

02-10-2003, 01:36 AM	#14
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	the 200 is not stronger in stock form...but a better tranny IMO.

02-10-2003, 10:22 AM	#15
smokekiki Mike Join Date: Jan 2003 Location: west chester pa Posts: 2,473	It is only a couple years of 200's that are stronger.Mostly the ones from the grand nationals.I have a 700r behind a 450hp small block with no problem.Has close to 18000 miles on it. __________________ 70'c/10, 71 suburban4x4 402bb, 72suburban 4/6 drop, 72k/5 4x4 blazer 4" lift 35 tires



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