Hey guys this is my first post so bear with me please. I have a 1999 siverado with a 5.3 . it shifts hard 1st to 2nd when it is cold (live in minnesota) when it warms up it shifts fine. if I put it in tow/haul mode it realy ****s hard when cold. I changed filter and fluid no help. truck only has 44,000 miles on it.
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Welcome to the forum!!! The hard shifting probably because the when the fluid is cold its like molasis in an igloo.And when its in tow mode it shifts harder/faster so the truck doesn't lose momentium while towing something heavy.
'95 1500 Silverado, 350, flowmaster Force II exhuast, S&B CAI.
I dont know about the cold cause I live in Phoenix but mine does shift harder in tow haul but I cant say it slams. I know there is something in the filter area that controls firmness due to the flow of the fluid but I cant remember what it is. Hopefully someone smarter than me will know more.
01 Silverado 5.3L 4X4
01 Camaro SS LS1 SLP
70 Nova SS 350
Mine doesnt have a "hard" shift actuallly it seems barely noticable that it shifts at all. the tow haul mode is more noticable and i like the way it feels.
i dont know much about transmmisons but from what i have read the 4l60e trans is a weak trans. you might want have a reputable shop look into it.
2006 Chevrolet Silverado Ext. Cab LT3 VortecMax (LQ9), Black, K&N 63 series intake, 40 series dual in dual out Flowmaster, Leveled on 295/70/17, Line-x, SS cluster, corvette servo. Blackbear 93 Tune
There are two possible solutions.
First; have the PCM flashed with updated software that is designed to address this issue, have the dealer reference GM Document ID # 585532 for further reference if needed.
If that doesn't resolve the harsh 1-2 upshifts then have the transmission pressure control selenoid replaced.
chevy truck shifting hard.
I have a 01 silverado 5.3 engine, mine will shift like in tow mode(longer shift points) in the winter time til it warms up.Dont shift hard. In the manual it says its suppose to do this til it warms up. maybe this is what you are talking about.??
The cold circuit simply raises the RPM's at each shift slightly to warm the engine faster this reduces emissions and improve heater performance, it should not make the transmission feel as though it is "slamming" gears or otherwise shift objectionably harsh, this feature is also only active when the temperature is 32F or colder.[/b]
thanksZX1100F1, I wasnt sure how he meant it. Along with the cold curcuit,
Mine will also slam if I have been driving for sometime if I hit passing gear hard or going up steep hills where it shifts to passing gear, after that, when I take off from stops it will slam into 2 and hard to 3rd just normal take off. Once I shut the ignition off and restart it, its usually fine. Sometimes the check engine light comes on, sometimes it dont. But that usually stays on til cleared. I get code P01870.
If you are getting DTC P1870 this indicates a slip condition inside the transmission which can be casued by numorous things such as:
Slipping band or clutch.
Incorrect fluid level.
Torque converter clutch malfunction.
A faulty converter clutch valve.
A faulty turbine shaft o-ring.
A faulty TCC or PWM selenoid.