overdrive transmission swap ? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

rddaves54 · 03-20-2014, 05:43 PM

I was wondering if there is a automatic transmission with over drive that would fit my 350, 1972 truck.

If so I might think about swapping it out to have better highway speed and mileage.

TobyArnot · 03-20-2014, 06:07 PM

Absolutely. 2 best options: A 200R4 or a 700R4. I just put a 200R4 in my stepper and it works too well. Truck has a 3.08 gear and I am seriously looking for a 3.73 rearend. There is a ton if info on the web. Favorite site is : http://www.bowtieoverdrives.com/index.shtml
.
You can find every thing you need from their website. Installation is pretty straightforward, most important is the setup of the TV cable from the trans to the carb. Read alot and go for it!

hugger6933 · 03-20-2014, 09:33 PM

the 700R4 is more popular and more populus if you will since they came in Trucks up to 7200 Gvw and Caprices, Camaros ,Astro vans ,Full sized vans,Vettes, you starting to get the picture? It was in production from 82-3ish until 93. The 200R4 is a lot less common trans but closest to a bolt in from what I hear even the driveshaft is the same length as the one for the TH350. the cross member how ever does have to be moved back and a hole drilled to place all the bolts back in it. Also i think that a longer speedo cable has to be installed as the speedo gear in on the very tip end of the output shaft of the 200R4. The 22R came in cars like the Monte Carlo SS Buick regal and the T type regal and the Grand National [both being turbocharged so the trans are really tough] Also the Olds custom cruiser Buick wagons the large cars full sized cars that still had engines other than the corporate 305 chevy. A lot of these trans have dual bolt patterns so that they can bolt to any motor GM makes that makes it even more of a value used. Jim

brad_man_72 · 03-21-2014, 12:19 AM

Apparently I don't say this enough, have a driveshaft shop modify your current driveshaft.

gysgtc · 03-21-2014, 05:50 AM

I did the 700r4 swap in my 72 lwb. Like mentioned above drive shaft has to be shortened about 3" and tranny support moved back. I have 3:08 gears that I am going to have replaced with 3:73. In the hills of West Virginia it bogs down to much in overdrive.

19GM71 · 03-21-2014, 06:53 AM

I don't want to hijack your thread, but I also jut swapped in a 700R4 from an 87 chevy half ton long bed with a 350 engine into my 71 stepper about 8 months ago. I also have 3:08 gears and will be swapping them for 3:73 as well.

My question to everyone is this, why did I Not have to shorten my drive shaft? I am glad I did not have to shorten it, but why not? My truck had a turbo 350 trans originally. I did have to move the cross member back about 3 inches. That is the only mod to my install.

Again, I don't want to jack your thread but maybe someone that knows why this is, can shed some light on the drive shaft question.

You won't be disappointed with the swap. Good luck and have fun.

SS Tim · 03-21-2014, 07:14 AM

With 3.08 gears your effective axle ratio, in 4th (O/D), is 2.16.
3.73 drops down to an effective ratio of 2.61.
4.11 (the factory ratio with the manual O/D) drops down to 2.87.

brad_man_72 · 03-21-2014, 02:05 PM

Quote:

Originally Posted by 19GM71

I don't want to hijack your thread, but I also jut swapped in a 700R4 from an 87 chevy half ton long bed with a 350 engine into my 71 stepper about 8 months ago. I also have 3:08 gears and will be swapping them for 3:73 as well.

My question to everyone is this, why did I Not have to shorten my drive shaft? I am glad I did not have to shorten it, but why not? My truck had a turbo 350 trans originally. I did have to move the cross member back about 3 inches. That is the only mod to my install.

Again, I don't want to jack your thread but maybe someone that knows why this is, can shed some light on the drive shaft question.

You won't be disappointed with the swap. Good luck and have fun.

The 700r4 is about the same length as a th350 with the long 9" tailshaft. That's the easiest explination. You could have also put the engine in a different mounting location, but you would probably know if you did that.

19GM71 · 03-21-2014, 02:32 PM

Quote:

Originally Posted by brad_man_72

The 700r4 is about the same length as a th350 with the long 9" tailshaft. That's the easiest explination. You could have also put the engine in a different mounting location, but you would probably know if you did that.

Ok thanks. I only changed the trans. So Apparently I had the 9" tail shaft on the 350 that I took out. Nice to know. Thank you.

Jimjific · 03-21-2014, 03:25 PM

I just posted this today for the 200-4R

http://67-72chevytrucks.com/vboard/s...d.php?t=621696

Jim

03-20-2014, 05:43 PM	#1
rddaves54 Registered User Join Date: Nov 2008 Location: Columbia SC Posts: 231	overdrive transmission swap ? I was wondering if there is a automatic transmission with over drive that would fit my 350, 1972 truck. If so I might think about swapping it out to have better highway speed and mileage. __________________ Chief mechanic for my, 54 Belair, 64 Corvair, 72 C/10Fleetside and 2002Tahoe. John 14:6 Jesus said, "I am the way, the truth, and the life. No one comes to the Father except through Me. My Book "Why Cancer is Not Bad Luck" by WestBow press

03-20-2014, 06:07 PM	#2
TobyArnot Quit if it's not FUN!!! Join Date: Jul 2010 Location: Indian Trail, N.C, Posts: 864	Re: overdrive transmission swap ? Absolutely. 2 best options: A 200R4 or a 700R4. I just put a 200R4 in my stepper and it works too well. Truck has a 3.08 gear and I am seriously looking for a 3.73 rearend. There is a ton if info on the web. Favorite site is : http://www.bowtieoverdrives.com/index.shtml . You can find every thing you need from their website. Installation is pretty straightforward, most important is the setup of the TV cable from the trans to the carb. Read alot and go for it! __________________ MY MOTTO: Eat it all up, Wear it out, Use the last few drops, Spend all you've got, Late in life, you'll think of the things you didn't do, not the things you did. - Get out and experience life ! . Robbie Robinson a.k.a. TobyArnot (Toe Bee or not toe bee)

03-20-2014, 09:33 PM	#3
hugger6933 Registered User Join Date: Oct 2008 Location: Marianna Arkansas Posts: 7,279	Re: overdrive transmission swap ? the 700R4 is more popular and more populus if you will since they came in Trucks up to 7200 Gvw and Caprices, Camaros ,Astro vans ,Full sized vans,Vettes, you starting to get the picture? It was in production from 82-3ish until 93. The 200R4 is a lot less common trans but closest to a bolt in from what I hear even the driveshaft is the same length as the one for the TH350. the cross member how ever does have to be moved back and a hole drilled to place all the bolts back in it. Also i think that a longer speedo cable has to be installed as the speedo gear in on the very tip end of the output shaft of the 200R4. The 22R came in cars like the Monte Carlo SS Buick regal and the T type regal and the Grand National [both being turbocharged so the trans are really tough] Also the Olds custom cruiser Buick wagons the large cars full sized cars that still had engines other than the corporate 305 chevy. A lot of these trans have dual bolt patterns so that they can bolt to any motor GM makes that makes it even more of a value used. Jim

03-21-2014, 12:19 AM	#4
brad_man_72 the boat guy Join Date: Jul 2007 Location: springfield mo Posts: 2,339	Re: overdrive transmission swap ? Apparently I don't say this enough, have a driveshaft shop modify your current driveshaft. __________________ 67, swb, fleet, tach, throttle, 5.3, 4l60e, 3.73's, fuel cell, 5 lug, p.d.b., 4-6 drop. great little truck 66, stevens drag/ski 18' silouette, 350, 2.02 doublehump heads. comp extreme marine 278 cam, vette 7 fin valve covers, old polished edelbrock intake, velvetdrive, casale v-drive, adj cavitation plate. 28, model a rpu project,

03-21-2014, 05:50 AM	#5
gysgtc Registered User Join Date: Apr 2010 Location: Sutton, WV Posts: 340	Re: overdrive transmission swap ? I did the 700r4 swap in my 72 lwb. Like mentioned above drive shaft has to be shortened about 3" and tranny support moved back. I have 3:08 gears that I am going to have replaced with 3:73. In the hills of West Virginia it bogs down to much in overdrive.

03-21-2014, 06:53 AM	#6
19GM71 Registered User Join Date: Jan 2014 Location: Stigler,OK Posts: 125	Re: overdrive transmission swap ? I don't want to hijack your thread, but I also jut swapped in a 700R4 from an 87 chevy half ton long bed with a 350 engine into my 71 stepper about 8 months ago. I also have 3:08 gears and will be swapping them for 3:73 as well. My question to everyone is this, why did I *Not* have to shorten my drive shaft? I am glad I did not have to shorten it, but why not? My truck had a turbo 350 trans originally. I did have to move the cross member back about 3 inches. That is the only mod to my install. Again, I don't want to jack your thread but maybe someone that knows why this is, can shed some light on the drive shaft question. You won't be disappointed with the swap. Good luck and have fun.

03-21-2014, 07:14 AM	#7
SS Tim Registered User Join Date: Aug 2010 Location: Edwards, CA Posts: 7,503	Re: overdrive transmission swap ? With 3.08 gears your effective axle ratio, in 4th (O/D), is 2.16. 3.73 drops down to an effective ratio of 2.61. 4.11 (the factory ratio with the manual O/D) drops down to 2.87. __________________ Thanks, Tim * VIN/Model Decoders * Power Team Charts (engine/transmission/gear ratio) * Post Your Pickup SPID Blazer SPID Suburban/Panel SPID * RTFM ... Read The Factory Manuals... download 'em here Highlanders Do you have a 1972 Plaid Pickup? Plaid Blazer ** Plaid Suburban

03-21-2014, 03:25 PM	#10
Jimjific Registered User Join Date: Aug 2013 Location: Albany, NY Posts: 145	Re: overdrive transmission swap ? I just posted this today for the 200-4R http://67-72chevytrucks.com/vboard/s...d.php?t=621696 Jim __________________ Thanks, Jim - 69 Short Step CST 350 AC/PB/PS - 69 Short Step 307 Man Column/PS



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