47re gov. Pressure

[89f150]

I have a 2000 dodge 2500. It has an 02 engine ECM&harness and pcm harness. The truck runs great, but when it is going for lockup the desired gov pressure goes to 845 but actual gov pressure it max of about 410-420. Does any one have any ideas on what would cause this? I've adjusted tv cable from one end to the other. Checked fluid level. I don't wanna sit here and swap parts if I don't need to. Trans is full billet shafts with triple disk. Engine is 6x18 s366

[joefarmer]

I don't recognize the pressure units. What is 845 or 410 in PSI?

[89f150]

Originally Posted by joefarmer

I don't recognize the pressure units. What is 845 or 410 in PSI?

Kpa 65.2 psi and 122.5

[Big Blue24]

Originally Posted by 89f150

Kpa 65.2 psi and 122.5

So the PCM is commanding 122.5 but only producing 65.2 psi, this tells me the pump is not keeping up with the fluid/volume demands on the system during lock-up and/or overdrive actuation.

I personally see an overall line pressure dip from 200 psi to about 155 psi during the overdrive shift on my 47rh. This is partially due to the fact that I'm shifting overdrive around 2800 rpm and the pump doesn't produce peak volume at that rpm range. I also have a stock pump body with 48re 10-lobe gears which probably flows similar to the stock pump setup.

[joefarmer]

Put a gauge on it and look at line pressure. That should tell you whether to troubleshoot pump or VB.

[89f150]

Ok so I have an update. I changed the filter and put 10 qts of type f and not I have lockup. But is it normal to have it downshift with lockup switch?

[89f150]

And what kind of guage and hose do you recommend I get?

[CorneliusRox]

If locked, it should never downshift unless you force it to (doing something other than using your pedals).

[joefarmer]

Any gauge that can read 220psi is fine. Use a 1/8 NPT adapter on the transmission's line pressure test port to connect the gauge.