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Best TH400 Valve Body Brands

#1
I bought a used turbo 400 transmission and it didn't have a valve body with it. What is a good, full manual, standard shift pattern brand to use in a Silverado trophy truck/prerunner?
 
#2
Manual valve bodies all operate about the same. Attention to tolerances and tuning for application is what matters. Talk to culhane or one of the more reputable builders. Manual valve bodies and aggressive shift kits will hammer the splines out of clutches and other components. So other upgrades will be needed to have a durable and reliable transmission.
 
#9
If you plan on street driving with a manual valve body I suggest making sure the rest of the drive train is super strong. The added traction will tear up parts with the hard shift that comes from a manual valve body. Or run some rock hard tires. If this is a dirt only truck than the tires will spin when shifting. My own experience with manual valve bodies is that while fun to drive. They are tiresome in traffic and hard on internal parts. Look for a valve body that will shift normally in drive and has manual mode when shifted. This will help protect the transmission and your wallet if street driving is part of the plan.
 
#10
If you plan on street driving with a manual valve body I suggest making sure the rest of the drive train is super strong. The added traction will tear up parts with the hard shift that comes from a manual valve body. Or run some rock hard tires. If this is a dirt only truck than the tires will spin when shifting. My own experience with manual valve bodies is that while fun to drive. They are tiresome in traffic and hard on internal parts. Look for a valve body that will shift normally in drive and has manual mode when shifted. This will help protect the transmission and your wallet if street driving is part of the plan.
I plan on only driving this in the dirt. I’m running 39” BFG’s on 17” KMC bead lock wheels.
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#12
I've always wanted to try a direct drive or dummy converter with a pedal to drop line pressure like a dirt modified roundy round car. Don't know if it's been done in a off road car. Bring the revs up and dump the pedal. Car leaves super hard always thought it would be cool in a desert truck.
 
#14
The 6.0 is right about there with 377 inches. The 4.8 and 5.3 are limited in bore material. Start with a bigger engine you will be time and money ahead. You will also gain durability by keeping more material in the bores. 6.2 gets you right about there. Swap the cam and springs throw a tune in it and you can achieve your power goal pretty easy and with a ton of reliability.
 
#15
Since you are running a computer controlled engine why not run a 4l80? Same basic case as a 400 and can be built into a paddle shifted 6 speed pretty easy. The 4l80 is actually stronger than the 400 in some respects. The Reid cased 400 that the big boys run uses 4l80 internals.
 
#18
The 6.0 is right about there with 377 inches. The 4.8 and 5.3 are limited in bore material. Start with a bigger engine you will be time and money ahead. You will also gain durability by keeping more material in the bores. 6.2 gets you right about there. Swap the cam and springs throw a tune in it and you can achieve your power goal pretty easy and with a ton of reliability.
I got this motor and transmission for really cheap and was just going to use them to mock up mounts, then I read this article on the 5.3L http://www.trucktrend.com/how-to/engine/1208tr-5-3l-bow-tie-builds-mild-to-wild/ and now I am on the fence if I want to build mine this way or go with the 6.0L. As for the 400 transmission, again I got it really cheap and couldn't pass up the deal. Although that 6 speed paddle shifter does sound pretty badass for a desert truck, lol. I've got plenty of time to figure it out cause I'm still doing fab work to the truck.
 
#19
Don't get me wrong. The 4.8 and 5.3 are no slouch. Plenty of power to be made with those motors. I was just stating that it's probably more cost effective to start with a bigger engine when the time comes to start chasing power. A larger engine will make more power at a lower r.p.m. where the truck needs it and still be able to turn enough r.p.m. to scream up top.
 
#20
Check out engine masters and car craft. There is almost always a new article about building big power on the cheap with l.s. engines. I swapped an aluminum 5.7 into a Honda s2k for a customer from the u.a.e. using water/meth injection and a cam swap. He wanted a "sleeper". The plan was to go hunt lambos and Ferraris. That car is /was one of the fastest cars I've ever been in. And I spent a couple years building fast ass street cars.
 
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