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Transmission won't go into gear when cold!

28K views 85 replies 12 participants last post by  KC10Chief 
#1 ·
I have a 97 Safari AWD that I just bought yesterday. It has 74,000 miles on it. It runs, shifts and rides great! Tonight, I was leaving work about 10pm here in Alaska. It was about 5 degrees out. The van had been running for about 5 minutes (I have auto start). I came out, got in and it wouldn't shift into reverse to back out. The RPMs went way up and it moved back a little, but nothing. It wouldn't go forward in drive either. Finally, after about a minute of revving the engine in reverse, it started to move. It was a little slow to go into drive, but it did and I was able to drive home. It shifted funny one time but after that when I started driving, but it drove great the rest of the way home. I got home and ran it through the gears. Everything seemed perfectly normal then. Any ideas? I'm pretty certain that the cold caused this somehow. Bad fluid? I'll be checking the fluids out tomorrow. Any thoughts on other things I could check?
 
#4 ·
GM's reply to several customers when I was working there: "warm up your vehicle."
 
#6 ·
Dexron 3 or Dexron 6 , Dex3 is what came in it , Dex 6 is GM latest upgrade per TSB is suitable for anything that uses dex 3 , I use Castrol , any quality brand name should be good, if you change the filter be sure to use a good quality filter with the fibrous material , not just a screen and NOT any cheap brand ,
 
#7 ·
Thanks! The O'Reilly's near me has Wix and AC Delco. The AC Delco is twice the price of the Wix. Is it worth it? Also, is there more than one transmission for these vans? I thought I had the 4L60, but one of the other options is an M30? Never heard of that.
 
#8 ·
4L60E is the same as M30 , just a different way of listing it , GM often calls it both

in the Gen 1 vans of early age they had a few choices , but all Gen 2 96 and newer have the M30
Wix are good so is Ac Delco , unusual that there be that much price difference , it should be 25 -30 dollars , before you put out your money have the counter guy bring out both and compare them
 
#9 ·
Well it just got worse. It is like the torque converter just unlocks while I'm driving. It won't get above 30 mph. It pulls fine through first and second and then it feels like the torque converter just unlocks. The rpms go way up. I'm typing on my phone now. I'll type more when I get home. Any ideas?
 
#12 ·
Also, I realized that the torque converter seems fine. It is shifting into a lower gear. It shifts into second and then when I'm up to about 20 mph or so, it shifts back into first. Guy at Napa suggested that it could be the mass air flow sensor. I have a check engine light as well. I am going to take it down to pull the code in a bit.
 
#13 ·
Just got back from O'Reilly's. The code I got was a P1870 for transmission component slipping. I researched a little on here and most other people are getting this code but not having transmission issues. I am definitely having transmission issues. It will not shift into 3rd or 4th no matter what I do. To get it to shift into 2nd from 1st, I have to drive it to about 25 to 30 mph with the RMPs way up, then let off the gas. It will then shift into 2nd and stay there until I slow back down. Transmission fluid looks good. I did have to add three quarts! I just bought this van and it was fine until today. I drove it last night and it was perfectly fine. Drove it on the highway and everything. It drove fine all the way home last night. It was parked outside last night and it was about 10 degrees outside. This morning, it didn't want to go into gear at first. Kind of the same thing it was doing at first. When it did it the first time, it was fine after about a minute or two. Not today though. Any thoughts?
 
#16 ·
Thanks! I had already read those threads. They just don't quite fit the problem I'm having. Most people that get the P1870 code, aren't having any shifting problems or they are having a hard 1-2 shift. I'm definitely having shifting problems that came on suddenly. The 1-2 shift is delayed, but it's definitely not a hard shift. Also, I reset the code with the scan tool. I drove the van another 10 miles or so to get home. The shifting problems are still there, but the code didn't come back. Any other ideas?

I have had this van since Monday. I haven't even put a half tank of gas through it. It was driving and shifting perfectly fine until this morning. I'm about sick over this. I haven't had problems with any vehicle for a long time now. This week, everything is going downhill. I have three vehicles and all have issues. My 96 S-10 just started leaking gas out of one of the injectors this week too. My wife's 08 G6 desperately needs the snow tires put on due to all of the recent snow we have had. I'm going to go do that now, and hopefully I'll have some more ideas from you guys when I get back! I'm very frustrated with vehicles right now.
 
#17 ·
Is it possible you could have overfilled the transmission? Did you add fluid, or drain it all and then fill it?

Overfilling the transmission is very hard on the fluid pump.

When I've had shifting problems, it's been a dirty shift body or a malfunctioning shift solenoid. If you were overdue for a fluid change, gunk could have accumulated in the shift body and it would need cleaning. If a solenoid is worn or lube is sticky, it could cause trouble shifting.

And the transmission won't warm up much until the rig's been moving for a little while and fluid has been circulating.

I've got to get that extra set of seats and those tires out of my garage and get the Safari in there before it gets seriously cold here in Our Fair Capital City so I can start the day with a warm and dry taxi. Weather forecast says temps in the low 20s around the middle of next week, after we have 6 inches of snow, followed by rain, followed by more snow; typical Rain Country winter weather.
 
#19 ·
Is it possible one of the shaft sealing rings is sticking when it's cold? The ones that GM told the drivers to warm up their vehicles was at about -5 F and colder. That was from technical assistance! Looks like you need someone with a lot of technical knowledge and a scanner to tell what exactly is slipping. To grab a straw, does the speedo work properly? I think these use the output shaft sensor for shifting and operating the speedo. If this trans senses bad slipping it may also default into limp mode which turns off all the electronics and gives you second gear and reverse so you can "limp" home. If it were mine I'd be removing the pan and opening up the filter to check for debris. If it's starving for fluid because it can't get through the filter it will behave very strangely.
 
#20 ·
Well, the past couple of times I've gone out to start it when it's cold, it goes right into gear. It just won't go beyond 2nd gear. It acts like it's going to shift into third, but third just isn't there. It revs way up high. I let off the gas and it goes back into 2nd gear where it stays. .

Today, I went and changed the transmission fluid and the filter. Of course, I didn't get all of the fluid. The fluid definitely smells burned. I just couldn't smell it on the dip stick. But when it came out of the pan, it smells pretty badly burned. There weren't any big chunks of anything in the pan but there was some fine black powder. Looked like clutch material. There was probably just enough in there to cover the bottom of the pan with a thin layer. There was also a layer of sludge stuck to the magnet. I disconnected the battery for a few minutes hoping that if the transmission were in some sort of computer controlled fail safe mode, that it would be reset. No change either.

What do you guys think? Sound toasted? I'm thinking I'll take it in and get a diagnosis done at a transmission shop. I've decided that if this transmission is bad, I'll just buy a new or rebuilt one and to the removal and installation myself. If that comes to pass, what else should I fix while I have it out? I think the rear main seal might be leaking a bit. Not sure. Thoughts?
 
#22 ·
Make sure you get a new torque convertor as well , that burnt contaminated fluid in it will contaminate your new trans , sometimes a new trans will come with new converter , but not always. add in a new Hayden 679 external trans cooler so this new trans will last you many years .
 
#23 ·
I'll be pulling the transmission on Thursday. I took Thursday and Friday off so that I can get this done. My S-10 decided to have a cracked cylinder head at the same time. It's been a fun week. I'm holding off on the S-10. It still runs and drives decently. It's leaking anti-freeze into one of the cylinders and chugs a bit. But I'll need it to transport the van's transmission on Thursday. Tonight, I went out to move the van and I could not get it out of park. I suspect that it was cold related somehow. It's about 5 below zero outside right now and the wind is blowing pretty good too. Definitely miserable weather. I let the van warm up for about 15 minutes and I went out and it went right into gear like usual. Perhaps some condensation froze something up in my steering column? I have no idea.
 
#24 ·
Listen for a click noise under the dash when you step on the brake. There is a solenoid on the steering column to prevent the gearshift from being moved out of park without stepping on the brake. Could also be a frozen cable. Heat from the trans melts ice in the jacket of the cable.
 
#25 ·
Well, whatever the problem was with the not doing into gear, seems to have been a one time thing. Everything was extremely cold when I tried that. I'll look into that later. My main goal now, is to get the transmission removed tomorrow and get it to the rebuilder. The guy told me that if I can get it to him by close of business tomorrow, he should be able to get it back to me by Friday afternoon. He seemed pretty familiar with 4L60-E issues. I called every transmission shop in town. A couple were rude or not helpful. That's all it takes for me to not give somebody my business. I chose this guy because I liked what he had to say. He was friendly, polite and seemed to really know his stuff. It is going to cost me $1,450 to have it rebuilt. A brand new transmission from GM was $1,850 but it would take a couple of weeks to get here and it doesn't have the upgraded parts. The rebuilder said he replaces all of the clutches and worn parts. He also installs a hardened sun shell and does the valve body mod to prevent the 1870 codes and hard 1-2 shifts. Is there anything else that I should ask for when I bring him the transmission?

How long does it typically take you guys to remove a transmission? I'm pretty mechanically inclined. I will also have my van on a lift and have access to one of those tall transmission jacks. Any tips on getting this thing out quickly so that I can get it to him in time? Anything I should know about removing the transfer case? Thanks!
 
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