thunderstruck507

iTrader: (18)

A local trans builder has been swearing buy these things. Until he mentioned it, I had never heard of them.

An example is the TransGo 46-MOD
http://www.transgo.com/products.php?...product_id=200

Does anyone here have any experience with them? Seems to me the PCM is adequate for most circumstance but one use that came up is in a friends' twin turbo 5.3 2005 GTO. The 4l60e was having issues which seem to be related to insufficient line pressure (despite the pressure being boosted in the tune) which might be due to the effects of the SD tune on a turbo vehicle. Trans has been rebuilt and now has one of these kits and all seems well.

jakeshoe

iTrader: (14)

Old news.
Great way to prevent trans failure when the tuner isn't smart enough to tune line pressure properly.

mrvedit

^^^ +1. I like that.

However, I think that a twin-turbo and any 4L60E will soon divorce.

thunderstruck507

iTrader: (18)

I don't know all the specifics of the tune, however the last I looked the pressure tables were the ones sent in the Magnuson tune and I am using the same tables for my car because I liked how they were set up. There is definitely no lack of line pressure in mine, if anything I have a bit much.

I was just curious as I've never seen this before now.

jakeshoe

iTrader: (14)

How do you know it has plenty of pressure by looking at the tables?

I can say with almost 100% certainty that it likely doesn't have enough pressure for a boosted application.

Been there, done that, learned that lesson, and solved that problem.

thunderstruck507

iTrader: (18)

Trying to learn is all. I don't know for sure that it had enough pressure.

That was what I was getting at, using the same pressure tables my 4l60e actually coned a set of Alto 3-4 clutches and steels. His were just worn a lot. Has me wondering if it might have been a problem with the electronics themselves.

There for a while he was running B&M Trick Shift fluid which might also be a primary culprit. Or the wear might have been mostly under very light throttle shifts?

I don't know because I have a 3600 converter, he had a 2800. Also at some point I am fairly sure I did go back and alter the tables to flatline from 300ft/lbs and higher engine torque.

Transmission tuning guides and information are not as readily available as most other tuning information so when something like this comes up that sparks the questions I try to learn more about it for my own use.

mkvamso

iTrader: (2)

With the vacuum mod on now the car shifts much better at all throttle positions
It could have been a poor transmission tune for a turbo speed density setup, I don't know enough about it, but I'm very happy with the way it works with the vacuum modulator.
I never had a guage on it before, so I don't know what the actual line pressure was, but like thunderstruck said, it was about as high as you could command it in the tune.
It worked great for over a year with the maggie, but died shortly after the turbo setup. It could have been a tune issue, or the addition of a few hundred horsepower.
Line pressure now is dangerously high, like 270-280 psi, but it's holding and shifting great at mid 700s to the tire