whats wrong with my stock auto tranny?

[LoneRanger]

truck runs great, I put it in gear and if its warm it will chirp the tires going into gear and stall the motor, or if its cold it takes a little "effort" for it to get into gear, then it wants to stall the motor?
its got to be a tranny prob. shifts fine through all 3 gears, downshifts ok, reverse is the same as forward will stall out if warm, or when cold will take a while to "grab".

thoughts?

L.R.

 

[half cab]

Check your transmission fluid level. I would suggest changing your transmission fluid, especially if it is dirty brown or smells burned . look closely at your fluid to see if it has metal shavings or brown/black slimy gritty sludge in it. This sludge is usually the friction material from the clutch packs and that would require a rebuild .

 

[Rustytruck]

If your tranny fluid levels are correct and you have a delay between shifting into gear and the tranny actually grabbing hold when cold this usually is your seals inside getting old and hardening and delaying engagement. This usually means a rebuild before you damage something inside or you get stuck someplace during your travels. The kicker with your situation is the harsh engagement when warm. This is usually caused by too high of an idle setting Baring that it may be a stuck valve in the valve body allowing full line pressure when your not supposed to have it. I fear your on your way to a rebuild. It just depends on your situation. If you have to pay someone to change the tranny fluid and pull and go through the valve body your 1/3 the way into a cost of rebuild. If your capable of pulling the tranny and rebuilding it yourself that is what I would do. That is most cost effective. When was the last time the tranny was gone through? If its been close to 10 years its probably due for a going through.

 

[74strokerbronco]

I'm thinking torque converter issue , sounds to me kinda like it's acting almost as if it's locked up. once in gear will it sit and idle in gear without having to hold it back with the brakes? you should only notice a about a 100 rpm drop from neutral to a forward or reverse gear . also what is your idle rpm, to high and you could get a chirp when engaged but should not be causing a stall in less you have a timing or vacuum leak issue.

 

[Viperwolf1]

I'...should not be causing a stall in less you have a timing or vacuum leak issue.

This is where I would start looking. Shifting the trans in gear puts a load on the engine. If it isn't running well enough to overcome that load it will stall.

 

[Broncobowsher]

Also check the vacuum advance routing on the timing. Straight manifold vacuum makes the engine easier to stall when going into gear. Should be ported vacuum. While at it check base timing. Often cranked up "for more power" and screws up drivability.

 

[LoneRanger]

thanks for the input guys! good stuff!

L.R.

 

[lowbush]

I'm thinking torque converter issue , sounds to me kinda like it's acting almost as if it's locked up. once in gear will it sit and idle in gear without having to hold it back with the brakes? you should only notice a about a 100 rpm drop from neutral to a forward or reverse gear . also what is your idle rpm, to high and you could get a chirp when engaged but should not be causing a stall in less you have a timing or vacuum leak issue.

I was thinking torque converter drain back as well, but C4 converters are non-locking so he would not get a lock up condition. I think it's vacuum I would check your vacuum and replace the modulator before going any further.