98 4L60E No second gear

[ChevyINSANE]

I have a 98 Chevy truck with a 4L60E. It has no second gear. I was sitting in park for about 10 minutes with the engine running, then put it in drive and it never shifted into second. It felt like it went straight to 3rd. I played with it manually until I figured out I had reverse, 1st, 3rd, 4th and torque converter lockup…just no second gear. My acceleration rate was medium and when I reach about 27-28 mph it would shift from 1st into 3rd. It has 230K on it so I rebuilt it with all the typical parts…frictions, steels, band, sun shell etc…still no second. I then pulled the pan back off and replaced the spacer plate and put in a shift kit. While I had it down I put a corvette servo in and did an air check. It worked fine. I could feel the band tighten. Both the 1-2 and 2-3 solenoids checked good at 23 ohms. I swapped their positions to see if it would make a difference. I also checked to make sure the 1-2 accumulator piston wasn’t stuck in its bore, the spring was new from the shift kit. It was fine. Put it back together...still no second gear. When I originally pulled the pan off for the rebuild, the pan was free of any debris and was very clean. I then drove it a couple of miles to a local transmission shop. They put their scan tool on it and drove it around the block. There were no codes and the ECM was calling for second gear. It doesn’t sound mechanical since almost all the parts have been replaced, rebuilt or inspected that affect the 1-2 shift. It sounds electrical. Is there anything I have missed? I would appreciate any help.

[maxwedge]

Did they have a bi- directional scanner and command second gear?

[j cAT]

Originally Posted by ChevyINSANE

I have a 98 Chevy truck with a 4L60E. It has no second gear. I was sitting in park for about 10 minutes with the engine running, then put it in drive and it never shifted into second. It felt like it went straight to 3rd. I played with it manually until I figured out I had reverse, 1st, 3rd, 4th and torque converter lockup…just no second gear. My acceleration rate was medium and when I reach about 27-28 mph it would shift from 1st into 3rd. It has 230K on it so I rebuilt it with all the typical parts…frictions, steels, band, sun shell etc…still no second. I then pulled the pan back off and replaced the spacer plate and put in a shift kit. While I had it down I put a corvette servo in and did an air check. It worked fine. I could feel the band tighten. Both the 1-2 and 2-3 solenoids checked good at 23 ohms. I swapped their positions to see if it would make a difference. I also checked to make sure the 1-2 accumulator piston wasn’t stuck in its bore, the spring was new from the shift kit. It was fine. Put it back together...still no second gear. When I originally pulled the pan off for the rebuild, the pan was free of any debris and was very clean. I then drove it a couple of miles to a local transmission shop. They put their scan tool on it and drove it around the block. There were no codes and the ECM was calling for second gear. It doesn’t sound mechanical since almost all the parts have been replaced, rebuilt or inspected that affect the 1-2 shift. It sounds electrical. Is there anything I have missed? I would appreciate any help.

with this skipping 2nd and going on upward to 4th/OD My guess is a valve stuck in the valve body. could also be worn valve body .

[ChevyINSANE]

I'm not sure of what type of scanner they had. If they could command second with a scanner and it would go into second gear, what would be the problem? The ECM maybe?

I've been thru the valve body twice. Once during the rebuild and then again when I did the shift kit. Its going from 1st to 3rd. I can feel it shifting onto 4th and then torque converter lockup.

[j cAT]

Originally Posted by ChevyINSANE

I'm not sure of what type of scanner they had. If they could command second with a scanner and it would go into second gear, what would be the problem? The ECM maybe?

I've been thru the valve body twice. Once during the rebuild and then again when I did the shift kit. Its going from 1st to 3rd. I can feel it shifting onto 4th and then torque converter lockup.

if the PCM had issues with grounding the return side of the 1-2 shift sol then you would get a 753 code.

did you check for proper resistance of this coil at the connector on the transmission ? I think its A and E .

I still believe this is stuck because any electrical screw up will throw a code. a stuck valve does not / can not be seen by the PCM feedback since it can only see electrical issues.

with the mileage on this I would replace both the 1-2/ 2-3 shift solenoid valves.

[ChevyINSANE]

I only checked the soleniods while they were out on the bench. But I did check the wiring harness inside the pan to make sure there were no bad conections or broken wires. I will check again at the connector and let you know. Thanks for the tip! I will also look into replacing both of the solenoids to eliminate the possibility of them being the problem.

[j cAT]

Originally Posted by ChevyINSANE

I only checked the soleniods while they were out on the bench. But I did check the wiring harness inside the pan to make sure there were no bad conections or broken wires. I will check again at the connector and let you know. Thanks for the tip! I will also look into replacing both of the solenoids to eliminate the possibility of them being the problem.

post when you fix it. loss of 2nd gear only is not a common failure. esp with no drive train code .

[j cAT]

do you fix it ?

[ChevyINSANE]

Since my last post, I replaced the valve body with another one from a local trans shop. Then I lost all gears but 1st and reverse. Put the old one back on and still just first and reverse. I was just missing second. Its just getting worse. Now my line pressure has dropped to 30 PSI in the forward gears and 60 PSI in reverse when I changed out the valve bodies. I pulled the trans out for the forth time and went completely thru it inspecting every piece. Pulled the front pump apart and it was perfect. To make it easier to understand, I will list all the components I've replaced.

Case
Valve Body (3) of them
Internal Wiring Harness
1-2 Solenoid
2-3 Solenoid
EPC Solenoid
Spacer Plate
Sun Shell
2-4 Servo
Band
ECM with new Flash
Along with normal rebuild parts from a kit...Steels, Frictions, Seals...ect......

I've replaced the case and used 3 different valve bodies. Still low fluid pressure. What am I missing? There are no codes and the ECM is calling for all gears.What else can cause low fluid pressure besides the pump, case and EPC?

[ChevyINSANE]

I remember a transmission guy telling me if you disconnect the EPC the fluid pressure would go to max. So instead of dropping the pan for gazillionth time, I simply unplugged the wiring harness from the transmission and started it with a pressure gauge hooked up. Instead of having 30 PSI in park, I now have 160 PSI!!! OK now I'm on to something but I'm not sure where to look. The EPC is brand new! But it must be on the electrical side for sure. As I mentioned before, the ECM has been replaced and re-flashed. I've checked wire continuity from the ECM down to the plugs inside the pan and all was good. Can anyone direct me to the next step I need to take. Thanks!

[Tblazer02]

Hi,did you ever resolve this problem. I have the same situation. Thanks

[j cAT]

Originally Posted by Tblazer02

Hi,did you ever resolve this problem. I have the same situation. Thanks

check the internal tranny wiring and the wires to the tranny connector.. inspect the a/b valves for wear .

[ChevyINSANE]

Yes I did figure out what the problem was. After all the new parts I threw at it, I finally replaced the internal wiring harness. I now have second gear again along with a bunch of needless new parts I purchased. I checked the old harness several times before I threw it away and never found anything wrong with it. It never did throw a code showing that there was a problem. I just didn't have second gear. So if someone tells you it will always throw a code when there's a problem, it is not true. At least in my case it wasn't. Hope this helps!

[j cAT]

Originally Posted by ChevyINSANE

Yes I did figure out what the problem was. After all the new parts I threw at it, I finally replaced the internal wiring harness. I now have second gear again along with a bunch of needless new parts I purchased. I checked the old harness several times before I threw it away and never found anything wrong with it. It never did throw a code showing that there was a problem. I just didn't have second gear. So if someone tells you it will always throw a code when there's a problem, it is not true. At least in my case it wasn't. Hope this helps!

good you found it . I did mention the wiring harness with these models .. also the ignition switch .. its all the same circuit low/no power to tranny/valves no upshift..

still this should throw code which , with a drive train GM coder reader is capable to output.

another guy in AK had this type problem It was the red wire to tranny connector had broken conductors in the insulation .. moving the wires he found it .. took him
a very long time to find it as it was not used for about 2 yrs..

[Tblazer02]

Thanks for any and all input. I looked at the connector at the trans and could not find any issues or bad connections. To recap, here is my issue. 4l60e on 02 trailblazer will not go into 2nd. Have to get speed high enough then let off for 3rd to engage. 3rd to 4th up shift and down shift is fine. Reverse is fine. If you put it in manual 2nd, it will not shift out of first. If you put in manual 3rd, it will not shift until speed is high enough to go into 3rd when you let off accelerator. After in 3rd, if you pull shifter into manual 2nd, truck goes into a neutral condition until it slows enough to drop into 1st. I have replaced all the internals during the rebuild. Rebuilt the pump, replaced all solenoids and installed new torque converter. After reinstalling the trans the condition was there upon 1st test drive. Since then I have replaced complete valve body and all solenoids, 1-2 accumulator, 2-4 servo, wiring harness. None of which helped the issue. I have no check engine lights or codes???? If anyone has any suggestions or thoughts on what to look at as I disassemble it again please let me know. Thoughts on ignition switch causing issue?? Or how to test. Thanks.