gothic_sera

Hopefully someone can help me here?

Solved the problem with my locked TCC, fine from cold this morning. So thats a result.

But I still have an issue with the transmission starting in second gear. It shift fine all the way up through the gears other than that.

If you put the lever in 1 then it will shift to first, but in any other position (2-D) it starts in 2nd.

I can't see anything wrong with my controller logic, datlogs show it's actuating the solenoids correctly and commanding the right gear, but unless the lever is in 1 it wont go in to 1st.

Please help a rather frustrated girl out!

AnotherWs6

iTrader: (17)

Can't offer help but my 2000 Silverado has done this for 15 years and it's fng annoying. I drop it to 1st manually every time I stop, it's just second nature at this point.

gothic_sera

Thanks... like you say, not much help, but good to know I am not alone!

I can't see any reason why from an electrical perspective.

With the lever in D the shift solenoids are in the correct configuration for 1st gear (A On, B Off), but it's definitely in second. When you get to the second gear shift point the solenoids switch, but the trans doesn't shift.

The log below shows the shifts. The green line in the top section is the current gear. The vertical line that runs all the way through is just before the 1-2 shift.

gothic_sera

Some line pressures which might help?

All at idle

Park 120psi
Neutral 125psi
Reverse 280psi
Drive 180psi
3rd 175psi
2nd 175psi
1st 175psi

gothic_sera

This transmission has the following modifications:

Transgo HD2 shift kit - with the exception of the pressure relief valve and pump modifications it's per the manual.

Upgraded sprags - assembled correctly - double checked when I stripped the transmission down for inspection.

Other than that a complete rebuild including new solenoids.

I can control the line pressures with my transmission controller, it's at it's defaults right now.

It shifts fine, other than not having first except in manual 1 lever position...

Controller is Megashift - it is commanding the 1-2 shift, and the solenoids are in the correct configuration for 1st gear with the lever in D with the car stopped.

2 questions really;
1. Any ideas what's wrong with it?
2. Am I likely to damage anything driving it as it is?

gothic_sera

Would a stuck/sticking 1-2 valve in the valve body cause this issue?

Anyone?

gothic_sera

Guess no one has any ideas then?

I'll pull the pan again and check the 1-2 valve. In the mean time I'll take it for a drive up the road and see how it drives...

gothic_sera

Be easier if I was in the USA.. run it over to a transmission shop and get them to take a look. No such luck over here in the UK - no one really specialises in these transmissions, and have no idea what they are looking at.

Main thing really is, am I likely to damage anything in by using the car until I get it fixed?

The wait for some VB gaskets is 10 days from the USA - doesn't make my job any easier. I don't really want to tear it down until I have the parts in hand.

gothic_sera

Took it for a drive up the road and everything is working as it should now...

Not sure what the problem was, but it's fixed itself...