Truck continuously stalls when shifted into reverse..........

[Bigbus]

99 sierra, 4.8 with Cai/exhaust FLT Level 7 4l60 and circle d triple disc 2800 converter.

i just recently installed the trans and converter and both seem to be performing perfect. however maybe coincidently the problem started shortly after the install.

The truck starts no problem although the idle seems to be a bit low 6-700 rpm gauge reading, but idles fine until i shift the gear selector into reverse upon which point the rpms drop and it stalls out (every time) when i go to start it back up it takes a few extra cranks to fire and usually have to give it some gas, like it dosent want to start back up again.

once its warmed up, selecting reverse usually isnt a problem
but every morning I go to start it up and leave for work, i go to back out of the driveway and she stalls, I can hold the brake and the gas a bit to keep the rpms up to keep it from stalling but the engagement is hard on the drive line and id rather not brake the billet output shaft on my new level 7.

also when its really cold (first started) giving it gas occasionally sounds like its missing until it warms up then i get full power and it runs great.

looking for ideas on what to check:
I recently cleaned the air filter and was thinking maybe i put too much oil on the filter and it possibly messed with the MAF ?
There are no check engine lights
I noticed the gas mileage is down a bit but that usually happens here in Canada with the cold and winter gas.


the motor is well maintained, fresh amsoil,plugs,wires, clean air filter,

could it just be a possibility of the idle being too low ? its always idled around 6-700 rpms since ive owned it, im looking into getting a blackbear or nelson tune within the next few weeks and want to make sure this issue is resolved.

[tanz45]

Is the neutral safety switch reading right? Harnesses clean and plugged all the way in?

Mine is off a lil bit and when i put it in reverse it jumps between Neutral and reverse. This causes my truck to surge and stall. But if i jiggle it so it reads Reverse only it is fine. I am just too dang lazy at the moment to crawl underneath to adjust it.

[Duct_tape123]

Low fuel pressure? Does it have good power WOT? I'd replace the fuel filter just for the hell of it. The new trans may be loading the motor down more when its cold with the thick fluid.

[aj06bolt12r]

If it only does it in reverse this may not be the problem but make damn sure the trans cooler section built into your radiator is not partially clogged. If it is the fluid pressure can back up and cause the tq converter to lock up and stall the engine when you put it in gear. My truck was doing this and I replaced the tranny and the torque converter on the advice of a tranny shop only to have it do the exact same thing. Replaced the radiator, problem solved. That was an expensive lesson but at least it gave me an exuse to install my 2800 converter.

[Bigbus]

Today she stalled out a few times shifting from park into drive.
its definatley surging between gears
im not using the cooler off the rad, im using a tru cool 40 k cooler.
not really sure how to prove that the neutral safety switch is working correct, but ill look at it.