95 4l60e unable to force limp mode

[OKAY]

Hello everyone. Friends 95 Silverado stuck in 1st after the high rpm / off gas 1-2 shift symptom. Before testing selonoids shouldn't I make sure limp mode works? I've pulled #20 fuse and trans plug but still stays in 1st.

Any help, I appreciate, thank you.

 

[GoToGuy]

Do you have the OE service manuals ?

 

[NickTransmissions]

Hello everyone. Friends 95 Silverado stuck in 1st after the high rpm / off gas 1-2 shift symptom. Before testing selonoids shouldn't I make sure limp mode works? I've pulled #20 fuse and trans plug but still stays in 1st.

Any help, I appreciate, thank you.

Does he have third gear when everything's plugged in?

Default should be 3rd for limp though if the vss is bad or not receiving power (due to it being unplugged or short issue) it defaults to first w/a no upshift condition.

 

[OKAY]

Does he have third gear when everything's plugged in?

Default should be 3rd for limp though if the vss is bad or not receiving power (due to it being unplugged or short issue) it defaults to first w/a no upshift condition.

What do you mean it defaults to 1st with a no upshift? Are you saying that if the vss is faulty/no power to vss it would be stuck in 1st? Replaced vss, haven't checked for power.. speedometer works. Also checked TPS.

Because what I'm trying to do, is force limp mode so it can be driven a short distance. I thought if you unplugged the big round connecter from the trans or pulled #20 fuse would put it into limp mode (3rd default w/ manual 2nd)

 

[OKAY]

Do you have the OE service manuals ?

We do not. Service manual will explain details of limp mode?

 

[df2x4]

We do not. Service manual will explain details of limp mode?

I would imagine so. The GM factory service manuals are available for download here for free. If you don't see the year you need in the original post, keep scrolling. Other members have added more years in later posts, we have all of them.

https://www.gmt400.com/threads/88-98-service-manuals.43575/

 

[NickTransmissions]

What do you mean it defaults to 1st with a no upshift? Are you saying that if the vss is faulty/no power to vss it would be stuck in 1st? Replaced vss, haven't checked for power.. speedometer works. Also checked TPS.

Because what I'm trying to do, is force limp mode so it can be driven a short distance. I thought if you unplugged the big round connecter from the trans or pulled #20 fuse would put it into limp mode (3rd default w/ manual 2nd)

Did he have third gear before unplugging everything or not?

 

[OKAY]

Did he have third gear before unplugging everything or not

Nope. Only 1st.

 

[NickTransmissions]

Nope. Only 1st.

Has anyone dropped the pan on that truck's transmission and/or air checked the servo at all?

If it only has first gear and speedo/DRAC/VSS/VSSB all work and will not upshift to 2nd even when everything's hooked up/plugged in then the 2-4 band is shot (3-4 pack prob is too). By pulling the plug you're simply testing the 3-4 pack for mechanical function...If nothing happens (i.e. no movement in limp / 3rd and no man 2nd) have your friend pull and rebuild the transmission.

But drop the pan and see what's in there if he hasn't already done so.

 

[OKAY]

Has anyone dropped the pan on that truck's transmission and/or air checked the servo at all?

If it only has first gear and speedo/DRAC/VSS/VSSB all work and will not upshift to 2nd even when everything's hooked up/plugged in then the 2-4 band is shot (3-4 pack prob is too). By pulling the plug you're simply testing the 3-4 pack for mechanical function...If nothing happens (i.e. no movement in limp / 3rd and no man 2nd) have your friend pull and rebuild the transmission.

But drop the pan and see what's in there if he hasn't already do