I've got a broken tranny in my 86 z28. It's the 700r4 that came in it stock. Well here is the deal. I'm going to replace it in the car and then rebuild the one in the car. I've read a few articles on performance between these trannys but I haven't been able to find anything on ease of installation. Would the TH350 and TH400 be a direct swap for my 700r4 or would there be a lot of work involved in these swaps.


PS. To think 5 months ago when I bought the car I was worried about replacing a front main tranny seal now I'm talking about rebuilding a transmission likes it's nothing...lol

 

I used a TH375-TH350 with a long tailshaft 9" instead of the more common 6", Hurst installation kit for the torque arm. By using the TH375/long tail shaft your able to retain the use of your stock driveshaft. This was by far the easiest tranny change and a crossover change at that I've ever done to any vehicle of mine. By myself I literally had it back on the road in 2hrs-it's that easy. Zero gain in the 1/4mi. though,

 

My 700r4 is gone and Im going to put in a TH350 like you did. I hear there is a conversion kit you can get from summit or jegs, do you know about it? Also some are saying get an Adjustable torque arm from Spohn,but I dont have another $375 after buying the tranny. What is this Hurst installation kit? how did it work? where can I get it?

thanks, encouraging what you say about the ease of the changeout

 

http://store.summitracing.com/partde...rt=BMM%2D30299

 

Either use the B&M or the Hurst, I think the Hurst is more expensive, but I got a deal e-bay from a guy, and I was very happy with the simplisity of the installation. It's been many mods ago, but if I remember correctly all it really involved was removing the tailshaft bolts off the rear of the tranny and bolting the bracket on, there are a few other peices for the torque arm and tranny mount, but very straight forward considering I did'nt have destructions to follow, I also installed a whole array of Aotumoeter Phantom gauges and the speedo cable is tricky to hook up, tight with no real room for priers or fingers but can be done. You'll have to tweak the tranny lines as they won't bolt right up, but it's minor to say the least. I want to say I had a little more room around the tranny/tunnel of the car with the TH350 also, seemed it was far easier to bolt back together than to take apart, but it was awile ago too so maybe the curse factors have been forgotten, but it could easily be done by even the mechanically challenged I keep waiting for a "deal" on an adjustable torque arm, but more than likely I'll change to a 4 link by the time I decide to really do something, it is expensive but they do sound like they are worth the money.

 

That's not right.

A 375 is a Turbo 400 with a 350-sized output spline. Uses the 350 drive shaft. Besides that, it's a 400 inside.

A 9" 350 is just that, a long-tail 350. It doesn't get a special number like the downgraded 400 did.

 

Thanks for pointing that out, I have zero trans skills except pulling/installing and slapping the shifter, I was told that's what they called them with the 9" tailshaft.

 

i just installed a built 375 in my 88 i used a umi crossmember and i made my own drive shaft out a 85 ford 150 4x4 which worked once i changed the yokes till i got my new shaft from pst ordered, which is 38.5 inch long center of ujoint to joint hope this helps

 

08-04-2003

Think he may have solved the problem given it was nearly ten years ago