olds 307 and 403

I am not fan of the so called bullet proof TH350 in stock form. I have seen too many fail behind little abuse and weak smog motors. They just looked decent compared to the awful TH200. I know they can be built cheaply and I have core that just lost 3 and has a slow reverse when hot. I wonder if a short tail 400 is better $$$ spent. I know a wrecker that has few. Throw a shift kit, a 3000 stall with remote cooler and hope for the best? I should probably upgrade the wimpy 7.5" driveshaft anyways. This would go behind a 424 ci, 403 stroker with big valve #6 heads and an agressive custom cam. Thanks

oldsmobiledave

There is a short shaft T400 from a 1968 Riviera in Lethbridge for $100 Canadian if you want a core & an OG code version from a 1969 442 in Calgary for $275 Canadian that he claims is ready to run if you are looking to go the T400 route.


I have a T350 that was pulled from a 72 Cutlass. It was running with no issues when pulled & has a shift kit if you want to buy another T350.


PM me if you want to chat.


Dave


Riviera T400 BT code


http://www.kijiji.ca/v-view-details....dId=1203039603



442 T400 OG code


http://www.kijiji.ca/v-view-details....dId=1173713423

droldsmorland

Key words stock form. A trans fails for many reasons. A properly built 350 or 400 will go a long way towards longevity so long as its built to handle the application. A used worn TH400 will fail just as easily as your 350 did. Look into TCI, Coan, Hughes and others for a blue printed and dyno tested 350 or 400 with A 2500 stall converter. These transmissions will have a warranty to boot. With all the hassle of R&R-ing a trans might as well do it once correctly. I have a TH400 TCI semi-manual valved trans with a 2500 stall TCI converter in mine. 15 years and running. It was built and serviced properly and lives comfortably behind a 500 ft/lb, 400hp, 400.

So you've given up rebuilding yours?

coppercutlass

My th350 has handled alot of abuse. I'm not a pro and I don't have experience but I built it and it works great

olds 307 and 403

Thanks guys, just kind of gauging which way to go. I am in no hurry, I need to get new heads for my Dakota first and get the 88 Cutlass stripped of it's drive train and interior this winter. The 70 is first priority needing the 2004R out of the 88 to become Dr Olds mileage machine till I get the 350 with a custom cam installed, along with 3.90 gears and posi.

olds 307 and 403

The only reason I thought TH400 is they are much stronger stock. How many $$$ in parts do you have in your TH350 Copper?

coppercutlass

Im running the B&M rebuilt kit with the shift kit and i ran it like that for 1 season with no issues. last spring a pump ring broke and i lost 2nd gear i pulled the trans out inspected it all and it looked great all i added was the hardedned race along with a new sealing ring . So its pretty much a stock th350 with little mods so to speak. I have probably no more than 300 in that th350 500 with the converter. Its an ebay vendor unit. "made in house" by winners choice transmissions. Its been a great set up so far. The only mod i made which i had equipment for was cutting the pistons to hold the max amount of clutches on a lathe . You can usually buy them already cut for like 25 bucks on ebay.

Professur

The much maligned 200 can take quite a bit of power if it's rebuilt right. http://www.dragracingonline.com/tech...anstech_1.html

olds 307 and 403

Makes sense since it is very similar to the TH2004R and same is true, can take big power IF built right. I will probably build it similar to what Copper did, extra clutches and a hardened race and 36 element sprag clutch.

coppercutlass

I ONLY HAVE the hardened race. Not the whole drum unit with the roller sprag. The new th350 I built has that unit but for the 250 bucks it's worth the investment. Also use the center support from a 700r4. Wider load area.

coppercutlass

I will have to send you the link. There is a really good rebuild video on YouTube. Very clear and no skips in the process of rebuild. Very descriptive.

Professur

I wouldn't mind seeing that vid too. I've got a 350 rebuild in the near future. A 350C, but I'm told there's a C delete that's fairly simple.

coppercutlass

Here is the video link. he has many other videos. All very informative. This is the re asssembly video. there is a teardown video. used this one to see how exactly he did the bushing install which is honestly the hardest part of the rebuild in my opinion. Unless you have the very expensive proper tools. I made my own custom bushing drivers for the stator bushings. I replaced mine to see how hard easy it was and it sucked but after killing a few sets of bushings i get it done lol. Bushings are not very expensive so order a few sets. The only specialty tool i have for the th350 is the low reverse piston compressor. Unless you make one its worth the 40 bucks. I also made my own little home made compressor to compress the drum assemblies. Trying to use 2 c clamps sucks .

transman74

The TH350, like any transmission can be made to take a ton of abuse. All depends on the thickness of your wallet. Keep in mind that GM put the TH350 behind small block engines, and if there was a big block up front the TH400 was then used. GM built millions of TH350's and with proper care they lasted a long time.
I would go with the TH 400, use either ALTO friction plates, or RAYBESTOS waffle lined plates, and perhaps for the forward/direct frictions, the high energy frictions used in the 4L80E, the HD welded front band, a new rear band, the 34 element intermediate sprag, replace the 3 Torrington bearings in it, all new bushings and a Transgo 400-1 shift kit. In other words, a complete rebuild with NO shortcuts.
On the converter, no sense ordering it until the engine/rear axle ratio/tire size specs. are finished. Then, find out from a converter builder what you need for YOUR APPLICATION. The 3000 stall might be OK, and then again it might not. Don't chuck your money away only to find out you've got to much converter. Contact Paul at T.C.S. in Langley, B.C. once your actually ready to order a converter. Pauls' number is 1-800-960-1177. They warranty their converters, build them in house (a lot of companies don't), and of course you'll be paying in Canadian loonies.
T.C.S. also has a performance kits already to go for the 400 and all other transmissions. Don't get caught up in the B&M, TCI, etc transmission kits. They buy all their parts from the same sources, that is BORG WARNER, RAYBESTOS, ALTO, etc. All the same parts, just different packaging.
It looks like you're spending some $$ on the engine, so don't cheap out on the drivetrain.

matt69olds

A TH350 is plenty tough to handle a stout 455 with nothing more than a good rebuild and some cheap upgrades. Machine the direct drum piston to accept 5 clutches instead of the factory 4, dual feed the direct drum (either internally or with a shift kit) pay close attention to the bushings and thrust washers, and make sure the endplay is correct. There are other cheap upgrades that can be done, depends on how serious you wnat to be.

grmchne78

I have had my Advance store reman. TH350, with A shift kit and a B&M Holeshot 3000 converter for years with no issues at all... it is behind a 455. I ABUSE it. It runs 8.30's in the eighth mile, driving it 50 miles round trip. I have never had a TH350 fail due to abuse, I've had them...wear out and start slipping (only two since 1984). I have three cars with the TH350 right now, my biggest gripe, is they all leak! I think they are pretty tough.

olds 307 and 403

I have seen them fail behind a couple of mighty mid 70's stock Olds 350's in their original cars. I may rebuild the one I have for a spare but a used short tail TH400 makes more sense in the long run. I nearly any of the classic transmissions leak somewhere.

coppercutlass

My th350 is nothing special and it's lived very well behind my 72 cutlass . Lots of abuse. Street strip deal. Just extra clutches, shift kit , hardened sprag race.

oldsmobiledave

Before you start your own T350 rebuild take a little time to read this thread and learn from one of the best T350 builders in the business.


It is by Jake (owner of Jake's Performance in Texas)


http://nastyz28.com/forum/threads/th...iy-post.53671/


This is the link to his services & online store.


http://www.jakesperformance.com/th350/


Dave

70cutty

I have Jake's parts in my th-350, so far it's been putting up with the abuse.

olds 307 and 403

Cooper's Cutlass is fast but my combo would put out more torque. The 350 is a well known trans, if I was really brave I will build the 2004R I have on a dolly for big torque.