I am unsure what the current OS is on the truck, have not scanned it yet. So whatever the stock OS was is what's still in it.

I was just going to do a write entire with a tune with a 12212156 OS that already had a 4l80 and then just do the wiring mods needed. My biggest concern was if my PCM would take the tune, and then be upgradable to a 3bar OS.

 

Hey when you where welding the flange did you weld the inside before you ported and cleaned them? That's where I'm at with my manifolds just wanted to ask.

 

Cool. That's what I'm doing. I haven't confirmed yet and won't know for sure for probably a week. All the info I have says it should be fine but I hate to say "yes", you license and it doesn't work lol. I'll post back probably next week with my findings.

http://www.hptuners.com/forum/showth...-with-4L80e-OS

"If you were going to license another OS I would have at least used the newer 2002 12212156 base operating system as it was the most universally used among all GM vehicles."

 

I have done it before but I usually don't. Can't remember what I did on my set. I get a little nervous welding flanges not bolted up to a jig due to the flange warping. Usually it won't move very much if it's already welded on the outside. If you're going to do it just make sure to do it quick. Keep as much heat out of the flange as you can. I would say 95% of the manifolds I've built I haven't welded the inside and they hold up fine. I've never had to fix a weld at the flange. I've built at least 40 manifolds.

 

Ok awesome thanks alot I'm just gonna grind them down then and not weld it then.

 

You're welcome. That's the route I would go.

 

I've been working on straightening out the vacuum lines. Stock intake, extra sensors and the stock harness are a mess. Not an easy way to make it look decent so I figured I'd at least make a few brackets. Also needed a mounting spot for a flex trans dipstick.







Driveshaft showed up last night!! woohoo!

4.00x0.125 6061-T6 DOM with Spicer XL U-joints (1350)

Also got a replacement trans slip yoke to replace the 3R U joint yoke I had before and I got a 1350 pinion yoke.

I can't say enough how great the service is at Driveshaft Specialist Inc, out of San Antonio. Very helpful with planning (probably had 20 emails), very responsive, great price and the build time was 3 days from time of order. I ordered last tuesday and it was at my door here in FL 5 business days later. That is bad ***.

Jeff Dusek is who helped me. not sure if they are a vendor on here, so PM me for his details if you're interested.

I plan on swaping the pinion yoke tonight and fitting the driveshaft. Have my fingers crossed.

Here's some pics

 

Everything looks great. I went with a 4" steel driveshaft but I have debated swapping to aluminum a few times. The bracket for the vacuum lines looks great too.

 

Ive bought 3 or 4 driveshafts from them and they have been great to deal with.

 

1 pc or 2 pc?