4r70w flare at WOT right before redline if...

[MalcolmV8]

Hey guys,

Been a little while. Thanks to everyone who helped me with 4r70w questions when I built my V8 AWD Ranger. It has a 2000 Explorer 302, 4r70w, and the AWD transfer case. I'm using a 92 Mustang ECC and the Baumman controller for the tranny.

Soon after I got everything running I developed a weird problem that I've never fixed. If I drive light throttle or even somewhat heavy footed everything works fine. If I drive WOT and hold it till red line it works just fine and shifts at 5000 rpm or so and everything's OK.

The problem is when I WOT and have it screaming up to read line and before it gets there I let off the gas. It either flares for a second or else it jolts quite violently like it jumped between two gears and couldn't decided where to go.

I've found if I'm WOT and something comes up that I have to let off before a red line shift if I ease off the gas it reduces the chance of it flaring or jolting and will sometimes shift normally. I've also found that if I WOT from a stop up to 80 or what ever and then jam on the brakes and stop and repeat over and over a few times and really get things nice and hot the problem goes away and I cannot reproduce it. However if I cruise for a few miles driving nicely and let the tranny temps come down a little I can reproduce it again, almost every time.

I have no clue what causes this or if it's something I can even fix? Not exactly a show stopper but it is annoying and would be nice to fix.

Thanks guys
Malcolm

 

[boominXplorer]

Is it all gears or a cirtain one? I snapped the accumulator spring for 2-3 and she would flare on occaision most of the time at higher RPMs. Found it when I put the Baumenn stage 3 in.

 

[MalcolmV8]

I believe it's only 2-3. I know never 1-2 that always works pefect, anything from light throttle to WOT and everything in-between. 3rd to 4th I don't believe ever happens. In fact I know it's not 3rd to 4th because at WOT that's shifting some where around 100+ mph (my speedo only goes to 85) and I'm always having the problems with my speedo needle still on the gauge.

So this accumulator spring, how hard or easy is it to get to?

Thanks
Malcolm

 

[Turdle]

If you install a bauman kit, you will replace it.
hint

 

[boominXplorer]

Drop the whole valve body and its right there. Baumenn kit doesn't replace it. Its a $6 part from ford.

Maybe Glaicer will chime in and give more insight.

 

[Turdle]

Drop the whole valve body and its right there. Baumenn kit doesn't replace it. Its a $6 part from ford.

Maybe Glaicer will chime in and give more insight.

Ooops
I just assumed it did, since my art carr kit did---kick me now

 

[MalcolmV8]

If you install a bauman kit, you will replace it.
hint

Well I don't really want to dump a bunch more money into this tranny. I was hoping to save up some day to purchase a performance built one to handle the power of my new motor I'm building, 331 stroker with a roots blower. Progress is slow right now, will be more than a year, maybe two before the new motor is ready so a simple fix for now would be cool.

 

[MalcolmV8]

Drop the whole valve body and its right there. Baumenn kit doesn't replace it. Its a $6 part from ford.

Cool. I assume this can be down with the tranny in the truck? I'll need to get a small part of my exhaust redone. The exhaust guy took the driver's side pipe and curled it under the tranny pan so to pull the pan I had to unbolt that section of pipe. However I had constant leaks where it joined the passanger's side so he finally welded it up nice and sealed. Now I can't exactly get the pan off Well not easily anyhow. I'll see if I can get that taken care of in the near future and then I assume a weekend job? Drop the valve body from under the truck and hopefully find a busted spring.