4R70W Smart People in here!

When shifting from 1st to 2nd gear, there's a hesitation. For example, to shift at 6800, you would have to shift 6000 for it to make the shift point. Any idea what could be causing this? It only does it to second gear.

Here is more detail about my setup:
Built 4R70W Automatic Transmission, Alto Red Clutches, Upgraded Intermediate Stub Shaft
Lentech Strip Terminator Full Manual Body w/ Trans Brake
Precision Industries Stallion Multi Disc Torque Converter w/ Balloon Plate and 3500RPM Stahl

Thanks in advance.
 
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sounds like an 1-2 accumulator piston/spring problem, do you know if the stock one was replaced with a stock one? Or was the Jerry mod recommended one used, or aftermarket.
Is there any vibration or is it like a free-wheeling hesitation? Cuz I've heard of some PI TC problems - it's possible
 
Good call, CobraRed...

When I did my J-mod, we left the 1-2 lower accumulator spring out. Couple that with a nice, firm 1-2 shift command in the SCT tune, and I have immediate shifts. So much so that even the manual guys that drive my car comment on how fast it shifts.
Don't get me wrong, it's not a bang....just firm and fast.
 
Good call, CobraRed...

When I did my J-mod, we left the 1-2 lower accumulator spring out. Couple that with a nice, firm 1-2 shift command in the SCT tune, and I have immediate shifts. So much so that even the manual guys that drive my car comment on how fast it shifts.
Don't get me wrong, it's not a bang....just firm and fast.

I chose to keep the 1-2 spring with the suggested J-mod piston. Very crazy firm 1-2 shifts, and i haven't adjusted it with the SCT yet since i dont have my cams that the tune is for in as of yet
 
Good call, CobraRed...

When I did my J-mod, we left the 1-2 lower accumulator spring out. Couple that with a nice, firm 1-2 shift command in the SCT tune, and I have immediate shifts. So much so that even the manual guys that drive my car comment on how fast it shifts.
Don't get me wrong, it's not a bang....just firm and fast.

I chose to keep the 1-2 spring with the suggested J-mod piston. Very crazy firm 1-2 shifts, and i haven't adjusted it with the SCT yet since i dont have my cams that the tune is for in as of yet


This whole automatic thing is new to me and I'm still trying learn about them. At the fear of sounding dumb, is the 1-2 spring in the tranny itself or in the valve body?
 
i took out the 1-2 spring in mine as well. with a little programming, i've got silky smooth shifts at low throttle positions and fast and firm shifts at higher throttle positions. works great.
 
I really appreciate everyone’s responses. :)

I have one more issue with this tranny that maybe you guys can give me guidance on as well.

When I have my foot pressed on the brake and go through the gears, it makes this sound I guess would be described as knocking or to me a can of rocks being shook. Any clue what this is? :shrug:
 
it say's in the first post that the car has a lentech full manual vb.that means the computer no longer controls any transmission functions!!!also,multi-disk pi converters are a little noisy.do a search on this or other sites and you see others commenting on this as well.stick with the stallion converter you'll be glad you did.these transmission will never shift immediately on command when shifting manually,no matter what vb is in it!:nice:
 
Mine shifts hard doing the 1-2. I actually toned it down -15 in my xcal 2 for winter driving, If I didn't I would be going sideways when the shift happens. I also turned down the over drive shift so it doesn’t clunk as much.
 
sry to steal this thread. Mine has 117K on it and I think it is on the way out. How much would a rebuild run me if I were t take it out and drop it off? what would you guys suggest to make it a little more stout. I am new to the automatic so anything would help (i.e. links/websites). anything I can do myself would be great. also recommend a brand and type of stall converter.

( I was going to go 5 spd but shipping costs are killing me where I can get a deal on the trans.)