CoonToot

Yes. Here is the timeline and occurrences:

Oct 2004 - total rebuild done after the stock sunshell broke. 5 pinion planets, the Beast sunshell, new bands and clutches throughout. The shop agreed to a 36 month, 36000 mile warranty under the condition that they could build it with ALL new HD parts. I bit and they built. Nelson tune on the PCM was not changed from where it was prior to the sunshell breaking. Everything was hunky-dory for 11 months and 10000 miles.

Sept/Oct 2005 - had a shudder/grinding sound in the driveline. Shifting was fine except at over 50% throttle. I can't tell if it is tranny or rear end, so I decide to throw money at the rear and replace the G80 with 4.10s and an Eaton. Did a self install of 4.10 (from 3.42) R&P and Eaton posi. No change in shudder/grinding. Well, crap, I guess I need to get the tranny looked at. Took it in,,,2nd band and 3-4 clutch pack was toasted from a cracked forward apply piston. Shop had never seen the HD steel version (which they installed on the initial build) fail. They rebuild, test drive and tell me to come and get it. I drive 55 miles round trip to work and back...the damn thing is flaring between 1st and 2nd. Discuss events with tranny shop...they are stumped as to what would cause such a quick death. I decide to get a tune from Nelson that sets the tranny settings back to 100% stock, including TQ mgt, BEFORE the tranny shop goes back in.Got an updated tune from Nelson to compensate for the new gears and newly added tire/rim combo that changed overall tire diameter.
Nov/Dec 2005 - tranny shop opens up tranny and cannot determine any physical reason for failure of the bands and clutches. We both decide to install the TransGo vac mod kit to attempt to A)eliminate the PCM control and inherent lag of line pressure raises and B) possibly get higher overall line pressures across the board. Tech replaces bands and clutches and installs vac mod kit AND a new 9.5" Edge 3000 stall converter to replace the stock 12" converter. Bolts it back in, takes for a test drive and it slips in every gear. Shop is closed next week for holidays (no biggie as my truck is an 'extra vehicle'). So now I am scrambling to determine what the heck I should do next. I seem to think the shop needs to check every step of the vac mod kit install. I must add that Dana at Pro-Built spoke w/the tech for 90 minutes prior to the most recent repair. Dana has gone above and beyond and I must publicly thank him for his help.
That's my saga...

James B.

iTrader: (1)

My stomach still turns every time I read about another 4L60-E draining another good person's checking account.

TeamTripp

Has anybody done the obvious and measure line pressure?

CoonToot

James,

I appreciate the sentiment. Going into it, I felt a local shop and a 36 month/36k warranty would be a good thing. I'm not so sure anymore...maybe the initial hassle of a 4L80E would have been the 'easier' path after all.

CoonToot

Not yet. It will be the first thing done on Jan 2nd when they return from vacation. The shop is skeptical that the Nelson tuned PCM might be the culprit - therefore the reason for my original question concerning PCM control.

TeamTripp

Once you replace the EPC with the Vacuum Modulator, the PCM looses ALL line pressure control. The only thing the PCM does now is control upshifts, downshifts and TCC lockup.

So you'll need to check line pressure with and without vacuum (min & max).

Merry Christmas BTW.

CoonToot

Sounds like a good plan. And Merry Christmas to you as well - mine will be complete once I escape from this tranny hell...