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Old Feb 1, 2012 | 07:37 PM
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Default TH350 Build

Since we had a recent thread here about $500 TH350 builds I'll post a small build thread with pictures to explain some points and show why it's unreasonable to expect to buy ANY decent rebuild for $500. Especially core inclusive.

Our transmissions start out with a core from a core supplier typically. We drop these off to be blasted before disassembly. Once blasted they come to the shop for teardown, cleaning, inspection, painting, prep for assembly, assembly, dyno testing, and palletizing.

This TH350 was torn down today, most of the parts inspected and cleaned, and will be assembled tomorrow.




Shown here is a common wear area. This case has quite a bit of wear where the low support beats into the case. If it is too bad, we scrap the case. In this case we will use a special low support with a plate added that catches a new area on the splines. This is an $80 part we have to add to most builds to be able to re-use the case. On our Stage II or higher builds we will use a different case with less wear.

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Old Feb 1, 2012 | 07:55 PM
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Basic Rebuild kit is about $85, plus filter, $3, roller clutch $10, band $4, additional clutch/steel $5, bushing kit $15, thrust washers $10, low roller $15, a few other misc parts (extra bushings, upgraded direct drum bushing, $80 low support to fix case, $35 governor, and in some cases possibly a pump at $120 for a reman).
Also all the pricing is wholesale for my shop that does over $100K in purchasing per year with this vendor.


Sun gear modified with double bushings for more stability of the geartrain.


Stock low support we will be replacing


Direct apply piston on the lathe to be turned so 5 direct clutches can be used.
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Old Feb 4, 2012 | 06:09 PM
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Upgraded low support to fix worn case issue common on TH350.



Wider low roller clutch.
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Old Feb 4, 2012 | 06:11 PM
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Nice quiet day in the build room trying to catch up...


And the dyno

Last edited by Jake's Performance; Feb 4, 2012 at 06:19 PM.
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Old Feb 8, 2012 | 12:15 AM
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What does the dyno check or test?
How much hp/tq can one of these hold?
Pricing?
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Old Feb 8, 2012 | 04:19 PM
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The dyno checks to see if it has all gears,
line pressure, cooler pressure and temp, fluid temp, etc.
I'm building two TH350s to train one of the new guys, they will be shelf units so we can probably make someone a little discount one one above and beyond the current 10% off.
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Old Apr 3, 2013 | 08:19 PM
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I'm going through the process right now of looking for a good th350 builder, thus the reason I stumbled upon this 2 year old thread. Looking for a good street strip build to hold the power of a carbureted, otherwise stock LS2.

We have a well respected transmission builder here in upstate SC (Cook's Racing in Cowpens SC) who all the upstate SC/Western NC racers swear by. He quoted me today a price of $350 to build a TH350 for me using my transmission core and converter core. I told him i wanted a simple build to support 400 hp. A couple of things I confirmed:

The price includes the obvious plate/disk/filter/vac modulator/ etc replaced and as he described a process of "heat treating the sprags".

Rebuilt mild torque converter

Shift kit

Extra plates or discs in areas they feel modification is needed

A few "tricks" to the valving and other components (his words)

And a complete case bushing set.

Now after reading this thread, it has me wondering how the hell the guy does it? He's been in business forever, has a continuous 2 week backlog, and I haven't heard a bad thing about the guy. For the local Ford guys he is building 800 hp capable C6 tranny's for less than a grand that are apparently bulletproof. How the hell is this?
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Old Apr 4, 2013 | 10:02 AM
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Originally Posted by eric8
I'm going through the process right now of looking for a good th350 builder, thus the reason I stumbled upon this 2 year old thread. Looking for a good street strip build to hold the power of a carbureted, otherwise stock LS2.

We have a well respected transmission builder here in upstate SC (Cook's Racing in Cowpens SC) who all the upstate SC/Western NC racers swear by. He quoted me today a price of $350 to build a TH350 for me using my transmission core and converter core. I told him i wanted a simple build to support 400 hp. A couple of things I confirmed:

The price includes the obvious plate/disk/filter/vac modulator/ etc replaced and as he described a process of "heat treating the sprags".

Rebuilt mild torque converter

Shift kit

Extra plates or discs in areas they feel modification is needed

A few "tricks" to the valving and other components (his words)

And a complete case bushing set.

Now after reading this thread, it has me wondering how the hell the guy does it? He's been in business forever, has a continuous 2 week backlog, and I haven't heard a bad thing about the guy. For the local Ford guys he is building 800 hp capable C6 tranny's for less than a grand that are apparently bulletproof. How the hell is this?

He must have zero overhead and like to do it for free.
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Old Apr 4, 2013 | 12:20 PM
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Exactly. Something isn't adding up for sure. Regardless, after all the reading and researching I have done in the last month on reputable transmission builders, I am probably going with one of your stage I buildups anyway Jake. I will be calling you probably today to discuss what I'm looking for. There's no doubt that you build them right (understatement). To me, paying several hundred more for that peace of mind is well worth it.
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