Why is line pressure lower for 2nd into 3rd - Tuning Forum

Forum Post / Reply
You must log in before you can post or reply to messages.
Why is line pressure lower for 2nd into 3rd
Monday, January 02, 2012 9:01 AM
I noticed that the line pressure is pretty close from 1st into 2nd as well as 3rd into 4th, (4t40e) but if you look at 2nd into 2rd its much lower. Looking at the SC reflash, at 320lbs of tq, line pressure is 86 for 1-2 and 88 for 3-4, but only 40 for 2-3. My stock tune was pretty close to that too with a much lower pressure for 2-3. Why is that and would there be any advantage or disadvantage to making them all about even?



12.6 @ 114.6 MPH


Re: Why is line pressure lower for 2nd into 3rd
Tuesday, January 03, 2012 3:42 AM
It is easier on the trans, but if you ever had a shift-plus or auto trans interceptor.....all gear changes were at a higher line pressure.





Re: Why is line pressure lower for 2nd into 3rd
Tuesday, January 03, 2012 3:54 AM
Yeah, I do have one (shift plus). Isn't what the shift plus does increase based off of what the PCMs tables have it at already? Basically just increase the PCMs values by a percentage? So with or without the shift plus, it would still be a lower pressure at 2-3. So why is the 2-3 lower than the other 2? Why wouldn't they all be the same or close to it? Dos it just not need as much to engage into 3rd for some reason?



12.6 @ 114.6 MPH

Re: Why is line pressure lower for 2nd into 3rd
Tuesday, January 03, 2012 4:00 AM
Setting one increase the values to a set number. I believe setting 2 just maxed out the line pressure for all shifts.

Whalesac should know for sure. I would ask him.





Forum Post / Reply
You must log in before you can post or reply to messages.

 

Start New Topic Advanced Search