4L60E automatic reverse problem

lesmore49 · April 12, 2005

I have a 1997 Chev. Astro that I have had since new. I have one problem with it . When the temperature gets to be about 15 degree F or colder and it has been sitting for more than 4 hours or so, I have to let it idle for a few minutes before the transmission will engage reverse gear.

During the winter when the average temperature is 20 below and more for months at a time (I live in Canada) I usually idle it for 5 + minutes before it goes into reverse. I don't even try to engage reverse without idling in the winter now.

I can engage drive right away, but not reverse.

I first had problems with engaging reverse in the cold in Jan./04 when the van sat outside in 42 degrees below weather without being started or plugged in. I was barely able to get it to crank over and catch and when I got it to run , after a minute or so I tried to put it in reverse. The tranny fluid (and everything else) was like molasses.

Reverse would not engage until it idled for about 5 minutes and now this is standard procedure after the van has sat outside in cold temp. for a number of hours.

What do you think the problem and solution could be? Incidentally, it shifts well and functions perfectly, other than this reverse problem. In the summer reverse engages as fast as drive.

Thanks for any answers.

snoman · April 12, 2005

I have a 1997 Chev. Astro that I have had since new. I have one problem with it . When the temperature gets to be about 15 degree F or colder and it has been sitting for more than 4 hours or so, I have to let it idle for a few minutes before the transmission will engage reverse gear.

During the winter when the average temperature is 20 below and more for months at a time (I live in Canada) I usually idle it for 5 + minutes before it goes into reverse. I don't even try to engage reverse without idling in the winter now.

I can engage drive right away, but not reverse.

I first had problems with engaging reverse in the cold in Jan./04 when the van sat outside in 42 degrees below weather without being started or plugged in. I was barely able to get it to crank over and catch and when I got it to run , after a minute or so I tried to put it in reverse. The tranny fluid (and everything else) was like molasses.

Reverse would not engage until it idled for about 5 minutes and now this is standard procedure after the van has sat outside in cold temp. for a number of hours.

What do you think the problem and solution could be? Incidentally, it shifts well and functions perfectly, other than this reverse problem. In the summer reverse engages as fast as drive.

Thanks for any answers.

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How is the fluid level as some trannies are very sensitive to it. If it is fine you may have a seal going bad on reverse clutchpak that leaks a lot until it warms up a bit and swells enough to seal properly.

After re reading your post I am more inclinned to go with a bad seal in clutch pack that you damaged in cold weather. I trick I used when I lived in montana many years ago was to add some kerosene to automatic tranny during winter to help oil flow better in extreme cold. It helps a lot and I would run about 10 to 15% kero by volume in it. In the summer it boils off anyway. I also used it in my snowplow hyd pumps to keep them functioning in temps down to 40 below and better.

GM-Tech · April 12, 2005

Move to Florida?

I agree, sounds like a hard or leaking seal that seals better when warmed up. And of course, it's easy enough to check the fluid level, so that's the first think I'd look at.

lesmore49 · April 16, 2005

Move to Florida?

I agree, sounds like a hard or leaking seal that seals better when warmed up. And of course, it's easy enough to check the fluid level, so that's the first think I'd look at.

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Thank you for your answers. Would a damaged or hardened seal require a complete rebuild or could the seal be replaced?

What will happen if I just keep on driving it? Will the transmission eventually fail or could it continue to work well as long as I warm it up in the winter.

Right now with morning temps about 45 to 50 degrees f, I just start the van up and put it in reverse immediately and it works well. Come the winter and I'm sure it's back to warm ups.

GM-Tech · April 16, 2005

If someone were going to tear the trans apart to replace that seal, it'd be foolish not to go through the whole trans and reseal it all, replacing any burned clutches (if any). The biggest expense is the labor to tear the trans down, whether you're replacing one seal or all of them.

Yeah, it will probably eventually fail. Maybe tomorrow or maybe not for a very long time.

lesmore49 · April 22, 2005

If someone were going to tear the trans apart to replace that seal, it'd be foolish not to go through the whole trans and reseal it all, replacing any burned clutches (if any). The biggest expense is the labor to tear the trans down, whether you're replacing one seal or all of them.

Yeah, it will probably eventually fail. Maybe tomorrow or maybe not for a very long time.

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Thank you for the advice. It is much appreciated. In view of your assessment I think I will drive it till it fails and then as you say , as the labour is very expensive, have it checked out completely and have any parts/seals that are shot or on borrowed time, replaced or rebuilt.

Lesmore