700R4 converter engaging when braking. Can cashapp you some $ for answers

[Fricii]

Make

Chevrolet

Model

C10

Year

1972

Miles

0

Engine

LS3

We recently installed a 700R4 in a ‘72 C-10. Everything is working fine, but we’re noticing an issue with the converter engagement when braking.

When you put your foot on the brake, it disengages the converter as it should. However, the second you let your foot off the brake it immediately locks the converter, and bogs the engine down.

This is out of my area of expertise, our mechanic/engine builder is out today, and the shop owner asked me to look in to the topic online. Most of what I’m finding are not specific enough to assist with our issue.

Any advice would be greatly appreciated.

 

[nickb2]

However, the second you let your foot off the brake it immediately locks the converter, and bogs the engine down.

Faulty check way valve from booster to governor, but since I aint a trans guy, I cannot confirm.

But my mind would go there.

Just throwing that out there.

The Brake Booster Check Valve: What You Need To Know (2021)

Want to learn about the brake booster check valve? Here’s what it is, what it does and how to fix the valve when it’s failing.

www.repairsmith.com

One of the most common symptoms I have ever seen related to a engine wanting to bog down or stall when releasing brake pedal, check valve.

Maybe the above link will say better what my french brain is trying to say.

Anyway, good luck, hope someone else chirps in. BP is our resident guru here in trans dept.

 

[grcauto]

Are you sure it's releasing when the brake is applied? How are you determining that? Does it not release with throttle?

 

[bp042665]

most 700R4 have a computer that read the brake pedal to engage and dis engage what year 700R4 did you use in this