I own a 99 F-250 light duty 4x4 with a 5.4L. When I had bought the truck it had numerous problems that I had fixed. One of which was a bad lockup in the converter. I installed a brand new ford converter and while I was at it I bought a transgo shift kit. I did the springs from the kit (in valve body only), drilled the 3 holes larger in the separator plate and installed the .500 boost valve? It's been awhile, sorry.. I also put in a new filter and fluid. I rarely drive it, but use it to tow an open car trailer and car (less than 5000lbs combined) occasionally. The problem I am having (empty or towing) is that when it is cold..first 5 or 10 minutes driving it will not shift from 1st to second on its own. I have to run the rpms up then quickly let off the throttle and it will shift. Sometimes as soon as i step back into it it'll jump right back to 1st. It does occasionally act up when it is warm too. The OD light starts flashing..which means I have a code, I guess I'll check that and post it too, it'll probably help you guys diagnose the problem. I am open to suggestions.. it is frustrating and I feel like I am damaging the tranny when it does this. My dad seems to think the valve body could be torqued incorrectly causing it to bind? I am certain I torqued it correctly last time I had the pan off. One other thing.. in the Trans-go kit there was a white spring for the boost valve (kind of an install if you want to spring) I have that in with the .500 boost valve, could this be doing it? All the other gears are fine, no other tranny issues. I'll try to grab the codes tonight, but I'd appreciate any advice in the meantime. Thanks again!

Nathan

 

Check for codes and if you have a grear ratio code.The small inner valve is sticking.This is in front valvebody.

 

Of course when I plugged the scanner in it drove perfectly. No codes at all. Level10, you think the boost valve is sticking? When I installed the .500 boost valve later I left in the "white" spring from the Trans-go kit i had installed with the shift kit. I wonder with the .500 boost valve and that spring if it might be too much? Might it work smoother with the stock boost valve spring? In the trans-go kit it said install the "white" spring if the shifts are harsh at low speeds/light throttle (i.e. driving in a parking lot) What can I do to get the boost valve to work smoothly, can I lap it in the bore with some fine valve grinding compund? The .500 valve does have o-ring seals in the valve body bore so I doubt it's leaking down. Anyone have the torque values and pattern for the valve body? I think I did it to 86 inch/lbs and jumped around the valve body alot. Thanks
Nathan