TH350..good/bad???

[broncoman6524]

I have a built th400...i love it, if im standing on it in the rain when it shifts it breaks the tires loose.

IT's stout as hell too...gonna put a cooler and a gauge on soon to help it out some more.

my 700 died and i talked to the guy at the tranny shop an he talked me into the 400...glad he did, strongest of the bunch, but like as said before no OD

 

[RGV72BLAZER]

here are the pros cons from what i've read and everything

700r4
not as strong but i have a shift kit(50 bucks more)
o.d. so good on and off the highway and gearing isn't AS important as a 350
its not bad, it really isn't, wheels great for mud IMO and great on the road
low rpm

350
you have to find one and rebuild it
its crap off the line
****ty on highway
stronger for offroad
high rpm

I want you to explain each of your points made above...please...












Anyway, if you want the ultimate strength, swap out to a TH400, which will mean changing the splines on the 205 or swapping out the whole case...if not just upgrade your 700R4. you have 10 bolts, I'm sure you can make that 700R4 survive. They're just more $ to build.

 

[Gaffed]

So some of the later th350's came with a lock-up tq converter, I'm guessing the th400's also had this particular lock-up feature? I know that the lock-up trannies have a 4-pronge connector going into the side of them. Does anybody know exactly what years this feature was available?

 

[Gaffed]

This is the explanation of the differences between a 700r4/4l60 and a th350. Its explained by a friend of mine who has been a GM tech. for over 25yrs.
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Only the rear planetarys and center support are similar. From there forward, everything is different. The rear planetarys are used for 1st and reverse mainly. What's crazy as hell is that, while they have the same parts in the rear, they have different 1st gear ratios because they're driven differently from the front... if that makes any sense.

What makes a 350 a stronger transmission is that all of the gear ratios are achieved by applying clutches instead of using a band. The multi-disc clutches are just naturally stronger than a band. The only band in a 350 is the intermediate band, which only serves as a backup for the intermediate clutch when you pull it down to manual 2nd.

 

[AJMBLAZER]

Still not seeing a reason to run a TH350. A properly built 700R4 will do everything a TH350 will do and then has better low and OD...so unless you need the capability of a TH400 or 4L80E...why run something else?

 

[roadnotca]

This is the explanation of the differences between a 700r4/4l60 and a th350. Its explained by a friend of mine who has been a GM tech. for over 25yrs.
--------------------------------------------------------

Only the rear planetarys and center support are similar. From there forward, everything is different. The rear planetarys are used for 1st and reverse mainly. What's crazy as hell is that, while they have the same parts in the rear, they have different 1st gear ratios because they're driven differently from the front... if that makes any sense.

What makes a 350 a stronger transmission is that all of the gear ratios are achieved by applying clutches instead of using a band. The multi-disc clutches are just naturally stronger than a band. The only band in a 350 is the intermediate band, which only serves as a backup for the intermediate clutch when you pull it down to manual 2nd.

Good tech tid-bits. That'a probably why my TH350 survived a car torque convertor.

 

[Gaffed]

Doh! I should of taken some pictures of the teckpak adapter before I installed it. Seems like a quality adapter. Crossmember fit in the exact location as advertised.

I'm using a 2wd th350 with a 6" tailhousing/241c transfer case, cut the output shaft down to the specified length, then bolted everything together. Will know tomorrow if the transmission works. <---Oops!