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Another hard shift from 1st to 2nd. Plz Help me!

87K views 39 replies 30 participants last post by  SainT 
#1 ·
Hello everyone!
I'm new to this site but I have been reading lots of posts about hard shifting on this forum and most everyone seems very knowledgeable.
Okay, I just bought a 2002 Astro van with 230xxx hyw miles on it. (she drove a hour to work everyday)
the transmission was rebuild about a year ago (have paper work) and there is proper amount of fluid and it is still clean. Now, when rebuilding the
transmission do they replace the solenoids, valves and all that other stuff? (sorry I'm a noob). I'm having issue with hard shifting from 1st to 2nd. other gears work okay. there is no dummy lights on and it does it all the time, when i first start the van or drive 100 miles. I've read that it could be the 1-2 solenoid , shift valve, valve body, cpu, even cat. (I hope it's the catconv or solenoid :pray: ) I don't think cats ever been changed out and it doesn't have that much acceleration. but I don't know when the last time it had a tune up neither. would a tune up fix this problem? Man I just want to pull all my hair out!:banghead: Please Any input would be very appreciated!!!
Thanks in advance.
Julius K
 
#4 ·
hi there. 1st off, a rebuild means everything but the housing is replaced. 2nd, if you had it rebuilt a year ago, you should bring it back to the one who rebuilt it. chances are faulty parts. if they don't honor some sort of warrenty, then they are not reputable.
 
#5 ·
The most common problem in the 4L60E transmission is common and easy to fix. If a solenoid fails, it fails, there is no shift. Try running the truck through all the gears manually to make sure that they all work. The problem you describe is the TPS (throttle position sensor), it should move smoothly, it not replace it. Easy fix.

The other usual problem is that the separator plate between the valve body and case gets wear from the ball bearing type valves hitting the separator plate. Aftermarket balls are made of Viton and do not do this. Easiest fix is a B and M shift kit as they supply a new separator plate and Viton balls.

Contrary to what cowboy dan said, the only things that are routinely replaced are clutch plates, rings, seals, gaskets. The electric solenoids are cheap and easy to replace, they are tested simply by applying voltage to them, if they work, they are usually replaced.
 
#7 ·
Hello,

I'm the original owner of a 97 astro. I had the same problem, hard shift from 1st to 2nd. It first happened around 30k, they (the dealer) said it was the shifting valve body. Like clock work it happened again around 60k, thankfully I had the extended warranty. At 90k again, no warranty. I won't bore you with Chevy's response or lack there of to this issue. Took it to a reputable Trany shop, was told that inside the shifting valve body there is a piston (don't remember exactly what it does) that wears out the cylinder wall inside the valve body causing the piston to bind. This hang-up causes the computer to think that the trans is slipping, inturn it increases the hydraulic pressure there by causing the hard shift. They installed a kit in which they bore out the cylinder install a steel sleave in the valve body and replace the piston. About $360 back in 2000. They told me this problem was quite common. The van now has 226k, thats 131k miles and 11 years on the repair, it has never missed a beat.

Hope this is helpful.
 
#9 ·
see, this happens all the time. should it be a recall? yep. is it? nope. but thus far, this is the best answer to this common problem. i think it should be sticky, as there are always new posts of simular problems. i would hate to see this (good info) get lost. it is the most comprehensive explanation i have read. thanx bobbya. it may not be the answer to all hard shift problems. but it is common.
 
#10 ·
bobbya said:
Hello,

I'm the original owner of a 97 astro. I had the same problem, hard shift from 1st to 2nd. It first happened around 30k, they (the dealer) said it was the shifting valve body. Like clock work it happened again around 60k, thankfully I had the extended warranty. At 90k again, no warranty. I won't bore you with Chevy's response or lack there of to this issue. Took it to a reputable Trany shop, was told that inside the shifting valve body there is a piston (don't remember exactly what it does) that wears out the cylinder wall inside the valve body causing the piston to bind. This hang-up causes the computer to think that the trans is slipping, inturn it increases the hydraulic pressure there by causing the hard shift. They installed a kit in which they bore out the cylinder install a steel sleave in the valve body and replace the piston. About $360 back in 2000. They told me this problem was quite common. The van now has 226k, thats 131k miles and 11 years on the repair, it has never missed a beat.

Hope this is helpful.
The repair you are talking about is the "code 1870 repair" in which the TCC (torque converter control) valve hangs up, your converter overheats. similar problem can also occur in the isolator valve, however, i have never seen this on low mileage transmissions. I am wondering if your 1-2 acumulator spring broke,this was common in your year, especially the "yellow spring". the repair was to replace the seals/rings and put the "purple spring" in.I once worked at a dealership and it was common to cheat the factory by making small problems look huge and bill the factory for things that did not happen. Sad, then I came to learn that the same thing goes on in local garages even worse. this is particularily true in transmission shops. transmission rebuilds vary so much that one never knows what they are getting. To properly rebuild a 700r4 or 4l60e requires a lot of work on the valve body. for anyone getting a 4l60e rebuilt, i would encourage you to insist on the mechanic using the Sonnax SureCure 4l60E reconditioning kit. This is in addition to the usual rebuilt kit for seal, bearings, bushings, rings, clutches, etc.
 
#11 ·
I had the same symptom on my van for several years. Recently, the torque converter began leaking. A bushing had separated inside the converter(what I am told) and damaged the converter. After replacing the torque converter, the hard shift disappeared completely. A possibility perhaps.
 
#12 ·
I realize you have got your problem fixed now, but I had the same problem on 9/17/2011 and just wanted to let others know who may be reading this post as a means to fix their shifting problem.

My transmission was running a muck. If started first to shift hard into second and progressed to shifting hard in all the gears, if it would shift at all. If I was on the highway trying to pick up speed the transmission would shift into passing gear with the slightest acceleration. O yea, my engine idle was all over the place, going up and down and finally idling way to fast.

My problem turned out to be the TPS (Throttle Position Sensor). It is located on the drives side of the throttle body toward the radiator. You will need to remove the 'doghouse' for easier access. The two mounting screws are removed with a 'star bit', sorry not sure of the size.

I was concerned I needed to get into the transmission, but it was an easy $40.00 fix with a part from Advance Auto. If your check engine light comes on or is on that is a good sign the TPS is defective. I had Advance Auto connect the 'code reader' and there it was.
 
#14 ·
Hi, all.... Here's a little insight into the nature of the problem. My dad's 97 S-10 does this as well. A transmission shop told him that the valve body is made of cheap pot metal, and that there are check balls that are moved by internal pressure to control fluid channels, thereby controlling shifting. After awhile, these balls apparently damage the holes they move back and forth between (hellacious pressure) and sometimes don't seat properly or stick, causing the problem. It is a problem inherent to the 4L60E, supposedly there is a valve body upgrade that fixes this.

Hope that helps.
 
#15 ·
Daer Friend, I have owed 8 of these vans, all of different year models, but i had a 1998 that had the same problem that you are having, just after i had it rebuilt by a very good mechanic, we tryed a lot of things but the problem the entire time was a bad wireing harness inside the trans. It has a small harness inside the trans that runs to the shift silonoids and that was MY PROBLEM. But i must tell you that even after that was fixed we had determended that the trans case was defective, YES the entire transmission case that holds it all togewther was a lemon. After i got one from a wreck I NEVER HAD ONE SINGLE PROBLEM AGAIN.
 
#16 ·
Im telling you guys that i had a trans rebuilt by a guy who is very good. Mine did the same right after the rebuild and he and i did everything, replaced the valve body, replaced silinoids, and it was the wiring harness thats inside the trans THE WHOLE TIME. tHIS WAS 7 YEARS AGO AND IT COST UNDER 50.00 BUT THE GUY WHO REBUILT IT BOUGHT ALL OF THIS STUFF UNTILL HE GOT IT FIXXED. I saw him do the fix each time so i know 4 a fact he done all of this, Not just told me. So do what you gotta do, but I would try that at leary Lancaster
 
#18 ·
my 98 AWD Astro had to have a different transmission case rebuilt because the original one was that bad (torque converter was gold looking). transmission was rebuilt and has a hard 1-2 shift until it is warmed up. transmission shop installed a B&M Shift Kit. no CEL for the transmission only P0420 code (cat efficiency code.) if we drive in bumper to bumper traffic we will put the van in 2nd gear so we do not get the hard shift. it is not bad unless you are getting on the gas and take your foot off of the gas when it is about to shift then it is a pretty hard shift, otherwise it is not bad, shifts pretty quick now. was rebuilt at 125k miles and now had 217k miles and the transmission is still fine.
 
#19 ·
As of last Dec. I've owned my '99 ASTRO/V6/2WD/AUTO for about 3 yrs. It ran fine the 1st year, but during the heat of it's second Florida summer, it started 'kicking' HARD when shifting fm 1st-2nd. The rest of the shifts were fine. I have a good friend who's also a top-notch backyard mechanic. He kept telling me we needed to change the filter & fluid, but due to the economy, he's had to go north the last two summers to find work that pays a decent salary, so we hadn't gotten around to doing this. Too late now, :banghead: just a few days ago, I started backing up, but heard a loud BANG :eek: the next thing I knew I had NO REVERSE GEAR!! :screaming: Now I'm wondering if it would pay to rebuild this tranny, or get one out of a junkyard & hope for the best :?:
 
#20 ·
cookiemonster59 said:
As of last Dec. I've owned my '99 ASTRO/V6/2WD/AUTO for about 3 yrs. It ran fine the 1st year, but during the heat of it's second Florida summer, it started 'kicking' HARD when shifting fm 1st-2nd. The rest of the shifts were fine. I have a good friend who's also a top-notch backyard mechanic. He kept telling me we needed to change the filter & fluid, but due to the economy, he's had to go north the last two summers to find work that pays a decent salary, so we hadn't gotten around to doing this. Too late now, :banghead: just a few days ago, I started backing up, but heard a loud BANG :eek: the next thing I knew I had NO REVERSE GEAR!! :screaming: Now I'm wondering if it would pay to rebuild this tranny, or get one out of a junkyard & hope for the best :?:
Loud bang I am thinkin not so good. I would peel it apart myself see what happened. I am a different animal. I would rather rebuild something than chance getting a used one which may not be in any better shape than what I took out. Just do it right once, and get it over with for the next 20 yrs or so. :2:
 
#21 ·
drmmhmd said:
The repair you are talking about is the "code 1870 repair" in which the TCC (torque converter control) valve hangs up, your converter overheats. similar problem can also occur in the isolator valve, however, i have never seen this on low mileage transmissions. I am wondering if your 1-2 acumulator spring broke,this was common in your year, especially the "yellow spring". the repair was to replace the seals/rings and put the "purple spring" in.I once worked at a dealership and it was common to cheat the factory by making small problems look huge and bill the factory for things that did not happen. Sad, then I came to learn that the same thing goes on in local garages even worse. this is particularily true in transmission shops. transmission rebuilds vary so much that one never knows what they are getting. To properly rebuild a 700r4 or 4l60e requires a lot of work on the valve body. for anyone getting a 4l60e rebuilt, i would encourage you to insist on the mechanic using the Sonnax SureCure 4l60E reconditioning kit. This is in addition to the usual rebuilt kit for seal, bearings, bushings, rings, clutches, etc.
I installed a similar kit in my transmission a few months ago, it was a "P1870 code buster blister pack" or something along those lines purchase from a seller on ebay, it came with a mix of sonnax and trans-go parts, supposedly it was a better rebuild than the sonnax kit alone. Anyway I did the repair because the TCC would lock and unlock randomly at 50-60mph, I didn't have a code yet, but I figured it was better to fix it sooner than later.

The instructions for the rebuild said to drill out some of the holes on the separator plate, one of the holes was supposed to be drilled out to one size for a factory like shift and another size for a firmer shift, I didn't have the right drill bit for the factory like shift so I drilled it out larger for a firmer shift. After the rebuild was done I couldn't tell any difference in firmness of shifts except the 1-2 shift which is now pretty firm. Reading around some of the forums it sounds like a firm 1-2 shift is pretty common after a rebuild to resolve the P1870 code, it shouldn't slam into gear, but a firm shift is a side effect of the repair. The firm 1-2 shift may be my fault for drilling out the separator plate but I haven't been too concerned about fixing it, as long as I let off the gas slightly before the shift it's not too bad, it's worse when the transmission is cold and not as noticeable once it warms up.

If the OP has had the transmission rebuilt, the rebuild may have included a "shift kit" that firmed up the 1-2 shift, it could be something that doesn't need to be corrected.
 
#22 ·
Hey guys, I'm having almost the same problem with my 2001 RWD; it shifts hard out of 1st, but ONLY after driving it on the highway for an hour or more. I can drive it around town all day with no problem at all. I did get a dash light, and pulled 'P1870 Trans Component Slipping'

I'm wondering in all I need is bobbya & drmmhmd's fix?
 
#23 ·
Hard shift from 1st to 2nd, In cold weather while warming up first few shifts... Has a hard time finding idle at stop lights but runs fine. ( Its not getting worse and its not a rebuild situation.)

I did the obvious dropped pan changed 5lt of fluid added some lucas.

1) I want to believe it is the TPS as idle is off - threw light once with bad gas and clogged injector sometime ago. Doesn't post codes anymore since injector cleaned. But I still have an off IDLE. Computer has hard time finding an idle after battery disconnected - especially.

2)The yellow spring is part of a performance aftermarket shift kit ? Is that the side installed servo with a tricky seal ? Is this a culprit of using tow haul as a turbo button XD

I am thinking of perhaps doing both can any one link some instructions as this is common. I will make the videos With some guidance. Wanting to play with new camera :ty:
 

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#24 ·
I used to have the same problem with my 96 Astro. I've noticed that if you start your van up too quickly and put it into gear the hard shifting begins. Let the engine warm up and then put it into gear while holding the break until you feel it go into gear and you should be fine. Get it checked out.
 
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