Transmission Dilemma

Status
Not open for further replies.

Opie Knievel

Rum Fueled Midnight Mechanic and Moderator
Sep 6, 2010
1,512
1,859
113
Brodhead, Kentucky
As some of you already know, the TH350 in my '86 Monte Carlo went out last year. I've finally got some money rounded up to fix it. This morning I stopped by the transmission guy's place and got a quote. I was a little surprised by the price. $550. About a year and a half ago I had him build a TH350 for my truck and it costed me $425. I was expecting about the same price for this transmission as well and it caught me off guard when he told me that it would be $125 more for this one. I realize that this isn't that high of a price but it's more than I expected and it's pushing my budget. I was hoping to use the $125 for fluid and etc.

So, now I'm trying to decide what I should do. I have a few more options.

1. Buy a used TH350 for $250 with a 90 day warranty and maybe put a shift kit in it.

2. Rebuild the TH350 I have myself.

3. There is a 700R4 from a Camaro at work that I could probably get for around $300.

My questions and concerns.

-I've never rebuilt a transmission. The people I've talked to who have all say that the TH350 is easy to build.
To the guys on here who've rebuilt them, how hard is it? If I go this route I plan on getting a factory transmission rebuild manual and an aftermarket/performance rebuild manual.
Do you guys have any advice on building a TH350? Do you recommend any certain manuals? What special tools will I need? How much space do I need to disassemble and rebuild it? Is there a particular kit you would recommend?

- I've never had good luck out of 700R4's but I'd love to have overdrive in the Monte Carlo. I would probably put a shift kit in it too. Is a stock 700R4 with a shift kit worth my trouble to put in?

Right now the car still has the stock 4.3 V6 in it. I plan on putting a Vortech 350 in the car in the near future. It'll hopefully put out 350-400 hp. Probably close to the same torque. What do you guys recommend?
 

Texas82GP

Just-a-worm
Apr 3, 2015
7,981
18,676
113
Spring, Texas
I'm an overdrive man but you have a few more expenses putting in the 700R (crossmember, driveshaft, etc.). If you don't go with the 700R, then build the TH350 yourself. You don't rely on the car so you don't have the pressure of a deadline on you. I haven't built one but have read the same sentiment you have that they are fairly easy to do. I wouldn't be scared to try one. I'm told you can build/improvise most of the special tools.
 

ttype

Greasemonkey
Jan 30, 2017
239
223
43
Brockville, Ontario.
Opie since there is a stock 4.3 in your ride, does it have a th350C in it? did your truck th350 have a "lockup converter" in it?
i ran around in a t-top olds cutlass years ago with a 305 in it, and recalled watching the tach tone down by 200rpm just after settling to cruise speed... right at about the same time a "cruise control" would need to settle reaching a level spot in the road...
is there a slim chance the additional hydraulic circuitry require a bit more shall we say "finesse" when assembling or rebuilding as far as parts go?
like Texas82GP, i'm a fan of the overdrive too, but sometimes it gets to a point of $ that decisions are made for you...
a 200-4r swap will be a heck of a lot more cost effective for you since your driveshaft doesn't need altering this way, however the crossmember would need mods going the 200 route...700, not much more than a hacksaw(minimum) and a drill, and a pile of patience and 3.75-4" shorter driveshaft.
is the rear ratio in your car a 2.41, 2.29, 2.73?
an overdrive can work for you if it's a 2.73(or lower) however a lock'ed up th350C will have you some fine cruising rpm's with original type cruiser gears... food for thought? my pal has 4:11 gears in a lowered caprice, but the .5 overdrive in the 6 speed smartens that gearchoice right up, ending in a 2.05:1 final drive. that was his rationale with the gear choice... highway rpm.
 
Last edited:
  • Like
Reactions: 1 user

Opie Knievel

Rum Fueled Midnight Mechanic and Moderator
Sep 6, 2010
1,512
1,859
113
Brodhead, Kentucky
I'm an overdrive man but you have a few more expenses putting in the 700R (crossmember, driveshaft, etc.). If you don't go with the 700R, then build the TH350 yourself. You don't rely on the car so you don't have the pressure of a deadline on you. I haven't built one but have read the same sentiment you have that they are fairly easy to do. I wouldn't be scared to try one. I'm told you can build/improvise most of the special tools.

The no deadline part is one of the reasons I'm considering all of these options. The car has been down for months. What's a few more days?

Right now I'm leaning pretty heavy towards rebuilding the TH350 myself. I've always wanted to be able to rebuild automatic transmissions and I should save money doing it myself.
 

Opie Knievel

Rum Fueled Midnight Mechanic and Moderator
Sep 6, 2010
1,512
1,859
113
Brodhead, Kentucky
Opie since there is a stock 4.3 in your ride, does it have a th350C in it? did your truck th350 have a "lockup converter" in it?
i ran around in a t-top olds cutlass years ago with a 305 in it, and recalled watching the tach tone down by 200rpm just after settling to cruise speed... right at about the same time a "cruise control" would need to settle reaching a level spot in the road...
is there a slim chance the additional hydraulic circuitry require a bit more shall we say "finesse" when assembling or rebuilding as far as parts go?
like Texas82GP, i'm a fan of the overdrive too, but sometimes it gets to a point of $ that decisions are made for you...
a 200-4r swap will be a heck of a lot more cost effective for you since your driveshaft doesn't need altering this way, however the crossmember would need mods going the 200 route...
is the rear ratio in your car a 2.41, 2.29, 2.73?
an overdrive can work for you if it's a 2.73(or lower) however a lock'ed up th350C will have you some fine cruising rpm's with original type cruiser gears... food for thought? my pal has 4:11 gears in a lowered caprice, but the .5 overdrive in the 6 speed smartens that gearchoice right up, ending in a 2.05:1 final drive. that was his rationale with the gear choice... highway rpm.

The car came with a 200 metric. I killed it pretty quick. The TH350 I got to replace it was from a 78 or 79 Corvette. Non lockup.
If the rear end in the car is the original it's a 2.73. RPO GU2.

I would love to have a 200-4R. I haven't checked on prices yet. I'm guessing that it would need a little beefing up to last behind the Vortec though, right?
 

ttype

Greasemonkey
Jan 30, 2017
239
223
43
Brockville, Ontario.
factory 200-4r is much more beefier than thought of... input shaft is mondo strong compared to a stock 700's. the rest of the circuitry, well... not so much. it's the reason so many guys running the 4r's seek out the BR_ valve body cores. depending on the "core", shift governors determine shift points. gramma's 4r has an approximately 3200 shift point. perfect for a smogger vintage car that never sees more than a factory spec tune-up. monteSS,442/ho,and turbo regals differ in shift gov'r speed. the BR valve body is the goto as far as circuitry goes, and not held so dear as before because the "recipe" has been discovered. .67 o/d is hardly noticeable campared to .7 od, but the first to second drop is between the two.
 

Opie Knievel

Rum Fueled Midnight Mechanic and Moderator
Sep 6, 2010
1,512
1,859
113
Brodhead, Kentucky
factory 200-4r is much more beefier than thought of... input shaft is mondo strong compared to a stock 700's. the rest of the circuitry, well... not so much. it's the reason so many guys running the 4r's seek out the BR_ valve body cores. depending on the "core", shift governors determine shift points. gramma's 4r has an approximately 3200 shift point. perfect for a smogger vintage car that never sees more than a factory spec tune-up. monteSS,442/ho,and turbo regals differ in shift gov'r speed. the BR valve body is the goto as far as circuitry goes, and not held so dear as before because the "recipe" has been discovered. .67 o/d is hardly noticeable campared to .7 od, but the first to second drop is between the two.

I think I'll price check a 200-4R when I go back to the office in a few. Overdrive is really nice.
 

ttype

Greasemonkey
Jan 30, 2017
239
223
43
Brockville, Ontario.
my trans guy says "barking" the tires at anything less than WOT will break stuff and is completely unnecessary. i went the column shift route this time around because i'd rather go visit my favorite chiropractor for a chat(another cutlass aficionado) than shoulder work. the B&M shifter i had was getting to me after a while since it is stiff, then you add to it by getting the "other" shift linkages(column indicator) compounding the weight. my trans guy here, while not quite as famous as Art Carr, but held in just as high a regard. he likes the 200-4r too. transmission guy's wife's summer car is a pacer with i believe a 401 and 4speed manual. his pacer gets hauled around in an enclosed trailer behind a diesel pusher moho. he's been mentioned a few times over at the TR site.
 
Last edited:

L67ss

Royal Smart Person
Dec 8, 2016
1,350
420
63
I'm going the rebuild it myself route. Actually found a master kit minus converter for $110 on ebay
 
  • Like
Reactions: 2 users

pontiacgp

blank
Mar 31, 2006
29,270
20,391
113
Kitchener, Ontario
what about getting the used one for $250 and use that while you rebuild your th350. The $250 and the cost of the rebuild kit should be under $500 and then you have the used one as a backup.....and to sell once you have had a chance to try out your new rebuild.
 
  • Agree
  • Like
Reactions: 2 users
Status
Not open for further replies.

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor