Stuck In Second

zedbear · December 11, 2009

This evening my wife and I went out to eat in the truck, about a 2 mile ride. I had drove it earlier in the day and it exhibited no problems. Temperature was about 20 degrees.

The whole way to the restaurant, it wouldn't shift into 3rd. I took it up beyond 30 mph and it still would not hit 3rd. Only way I could coax it into 3rd was to blast the pedal for a second, and then let off. It was acting like it was in tow/haul mode. I turned that on and off a few times and it didn't help. We went in to eat, came out an hour later, started heading home......and it shifted fine, lol.

Any ideas what that was all about? I used to have a 99 Dakota that sorta did the same thing when in cold weather and before the transmission was warmed up a little: Wouldn't go beyond 2nd gear. But it sorta slipped a little in the Dakota's case. It ended up needing a rebuild. I hope thats not the case here.

99silveradoz71 · December 11, 2009

My 99 5.3 would do the same thing when cold- hold gears until it got warmed up. It was a normal feature.

zedbear · December 11, 2009

My 99 5.3 would do the same thing when cold- hold gears until it got warmed up. It was a normal feature.

It's normal to hold 2nd gear over 30 mph??? I've had vehicles that would hold 3rd gear when cold but not 2nd. Lame. I'll have to see if it does it today. It was very cold last night. Thanks.

zedbear · December 12, 2009

Went straight to the main road around the corner rather than going down 30 mph city streets today. Accelerated normally and it held 2nd all the way up till 35mph, then shifted hard to 3rd. Stopped at the light about 1 mile down the road. Accelerated again and this time it shifted normally.

I guess that could be normal but it kinda sucks if you just drive down city streets when first leaving in the morning. Trying to drive at around 30 mph while in 2nd gear = fail. Guess it will save on brakes, lol.

Nytemare · December 12, 2009

Went straight to the main road around the corner rather than going down 30 mph city streets today. Accelerated normally and it held 2nd all the way up till 35mph, then shifted hard to 3rd. Stopped at the light about 1 mile down the road. Accelerated again and this time it shifted normally.

I guess that could be normal but it kinda sucks if you just drive down city streets when first leaving in the morning. Trying to drive at around 30 mph while in 2nd gear = fail. Guess it will save on brakes, lol.

Or you could get up 10 min earlier and warm up the truck before you take off.

zedbear · December 12, 2009

Went straight to the main road around the corner rather than going down 30 mph city streets today. Accelerated normally and it held 2nd all the way up till 35mph, then shifted hard to 3rd. Stopped at the light about 1 mile down the road. Accelerated again and this time it shifted normally.

I guess that could be normal but it kinda sucks if you just drive down city streets when first leaving in the morning. Trying to drive at around 30 mph while in 2nd gear = fail. Guess it will save on brakes, lol.

Or you could get up 10 min earlier and warm up the truck before you take off.

I'm not one to just jump into a vehicle and go. Especially with this thing, due to the deluxe piston slap option this truck came equipped with, I'm even more anal about letting it run for a bit before driving away than I've been with other vehicles. However, I just found it wierd it would hold 2nd gear like that for so long.

Found this TSB:

Bulletin No.: 01-07-30-013A

Date: October, 2001

INFORMATION

Subject:

2-3, 3-4 Shift Characteristics During Cold Weather Operation on 4L60-E or 4L80-E Transmission

Models:

1999-2000 Chevrolet and GMC C/K Models

1999-2000 Cadillac Escalade with 4.3L, 4.8L, 5.3L, or 6.0L Gas Engine

(VINS W, V, T, U - RPOs L35, LR4, LM7, L04) and 4L60-E or 4L80-E Automatic Transmission

This bulletin is being revised to update the model years. Please discard Corporate Bulletin Number 01-07-30-013 dated April, 2001 (Section 07 Transmission/Transaxle).

Transmission operation during cold weather has been revised on these vehicles to provide taster engine warm-up and improved heater performance. During initial key-up, if intake air temperature (IAT) is less than 0°C (32°F), 2-3 and 3-4 upshift speeds will be affected as detailed below.

2-3 Upshift

^If the throttle position (TP) is less than 37 percent, the 2-3 upshift will take place at a minimum speed of 51 km/h (32 mph).

^If the TP is above 37 percent, the shifts will divert back to the normal shift pattern.

3-4 Upshift

^If the throttle position (TP) is less than 37 percent, the 3-4 upshift will take place at a minimum speed of 75 km/h (47 mph).

^If the TP is above 37 percent, the shifts will divert back to the normal shift pattern.

TCC Operation

If the transmission fluid temperature is less than 17°C (62.6°F), torque converter clutch (ICC) operation will not occur until the transmission fluid temperature is greater than 20°C (68°F).

When the engine coolant temperature (ECT) reaches 77°C (171 °F), 2-3 and 3-4 upshifts will divert back to the normal shift patterns. A brief description of operation is also included in the Owner's Manual.

99silveradoz71, you were right on.

Nytemare, I could let it warm up for 10 mins at these temps and it still would do the same thing since it still wouldn't meet the requirments listed in the TSB for "normal" operation. According to my little Scangauge, the trans temp takes forever to even reach 100F at current ambient temps and the coolant temp doesn't reach 171F at idle for quite awhile. But I know it's normal now so not a big deal. Just lame.

99silveradoz71 · December 12, 2009

Yeah I know it was odd when I had the last truck and would be going up the side street leaving work and she'd just be roaring away but not shifting unless you mashed it.

Nytemare · December 12, 2009

Yeah...that is a little strange....I also don't live in a really cold climate...it may dip down to 20F here...My truck usually warms up in about the time it takes to scrape the windows, warm enough to blow a little heat out of the vents anyway.

But yeah...if the Trans needs to get to that temp...your not gonna get it up there in the driveway...I thought it was just a coolant temp thing.

zedbear · December 12, 2009

Yeah...that is a little strange....I also don't live in a really cold climate...it may dip down to 20F here...My truck usually warms up in about the time it takes to scrape the windows, warm enough to blow a little heat out of the vents anyway.

But yeah...if the Trans needs to get to that temp...your not gonna get it up there in the driveway...I thought it was just a coolant temp thing.

Yeah, it kinda sucks. Let it warm up for about 5 mins while I took some garbage out today, then took off. Got up past 2K rpm at around 30 mph. I blipped the throttle to get it to shift, then let off and the engine went "ratttttlerattttle........" like a machine gun for a moment. Damn pistons. It did shift though.

Guess when its really cold, I'll just have to let it warm up forever or drive real slow until it shifts normally. Not a problem when I go right to the main road since it shifts past 35mph-ish but if I have to go down city streets at 30mph, it sucks. Wonder if there is a way to tune this "feature" out of the programming.

alwcurlz · December 14, 2009

My 99 5.3 would do the same thing when cold- hold gears until it got warmed up. It was a normal feature.

+1 Same thing here on my 99. When I was in Texas during last winter it would do that for the first 3 miles of driving, sitting in 2nd gear. The local transmission shop told me it was a normal feature to warm up the transmission. But, that was when it was 40 degrees or lower. Right now it doesn't do that because it's -16 degrees and I start it up and let it run for 10-15min before driving.

alwcurlz · December 14, 2009

Yeah...that is a little strange....I also don't live in a really cold climate...it may dip down to 20F here...My truck usually warms up in about the time it takes to scrape the windows, warm enough to blow a little heat out of the vents anyway.

But yeah...if the Trans needs to get to that temp...your not gonna get it up there in the driveway...I thought it was just a coolant temp thing.

Yeah, it kinda sucks. Let it warm up for about 5 mins while I took some garbage out today, then took off. Got up past 2K rpm at around 30 mph. I blipped the throttle to get it to shift, then let off and the engine went "ratttttlerattttle........" like a machine gun for a moment. Damn pistons. It did shift though.

Guess when its really cold, I'll just have to let it warm up forever or drive real slow until it shifts normally. Not a problem when I go right to the main road since it shifts past 35mph-ish but if I have to go down city streets at 30mph, it sucks. Wonder if there is a way to tune this "feature" out of the programming.

BTW, how cold has it been there? How long do you usually let the truck run before driving it?

zedbear · December 14, 2009

BTW, how cold has it been there? How long do you usually let the truck run before driving it?

It was in the teens to low 20's the last few days. Warmed back up to the 30's yesterday, though. Doesn't have any problems in the 30's or above.

In those very cold temps, I was letting it run for at least a few minutes before driving off slowly. Apparently I will have to make some adjustments to that. 30's and above, I'd let it run for a minute or so, then take off. Wasn't a problem at those temps.

Sorta sucks I'm going to have to burn through tons of gas all winter for lengthy warm ups all the time. Oh well.

Nytemare · December 14, 2009

BTW, how cold has it been there? How long do you usually let the truck run before driving it?

It was in the teens to low 20's the last few days. Warmed back up to the 30's yesterday, though. Doesn't have any problems in the 30's or above.

In those very cold temps, I was letting it run for at least a few minutes before driving off slowly. Apparently I will have to make some adjustments to that. 30's and above, I'd let it run for a minute or so, then take off. Wasn't a problem at those temps.

Sorta sucks I'm going to have to burn through tons of gas all winter for lengthy warm ups all the time. Oh well.

Or you could just drive around in 2nd until it warms up. It should be taching at what 2500rpm at 30mph. You'll burn less fuel doing that than letting it idle, and your not going to hurt anything.

alwcurlz · December 14, 2009

BTW, how cold has it been there? How long do you usually let the truck run before driving it?

It was in the teens to low 20's the last few days. Warmed back up to the 30's yesterday, though. Doesn't have any problems in the 30's or above.

In those very cold temps, I was letting it run for at least a few minutes before driving off slowly. Apparently I will have to make some adjustments to that. 30's and above, I'd let it run for a minute or so, then take off. Wasn't a problem at those temps.

Sorta sucks I'm going to have to burn through tons of gas all winter for lengthy warm ups all the time. Oh well.

I let my truck warm up because I like to get into a warm vehicle with cleared windows. Especially when it's below zero. It's easier on the engine and transmission in my view to drive them warmed up. If you don't want to run it in the morning because it uses extra time & fuel, you can just plug it in overnight or use a timer set to turn on 2 hours or so before you start it. A rule of thumb I used in the past on older carbureted engines was to plug it in if it was 10 deg or less so the vehicle would function better and last longer. Around town here you'll see many cars and trucks running in the parking lots of stores when it's real cold, like near zero or colder so they have a warm vehicle to get into.

zedbear · December 14, 2009

BTW, how cold has it been there? How long do you usually let the truck run before driving it?

It was in the teens to low 20's the last few days. Warmed back up to the 30's yesterday, though. Doesn't have any problems in the 30's or above.

In those very cold temps, I was letting it run for at least a few minutes before driving off slowly. Apparently I will have to make some adjustments to that. 30's and above, I'd let it run for a minute or so, then take off. Wasn't a problem at those temps.

Sorta sucks I'm going to have to burn through tons of gas all winter for lengthy warm ups all the time. Oh well.

Or you could just drive around in 2nd until it warms up. It should be taching at what 2500rpm at 30mph. You'll burn less fuel doing that than letting it idle, and your not going to hurt anything.

Pistons rattle too much when you let off the gas at 2K+ when it's not warmed up yet. Prob just better to let it run for a bit I guess.