PCM reflash

[fortcarp]

I have a '03 and was wanting to get the pcm reflashed for the latest software updates. I have the K&N 77 series cold air intake and have the resonator removed. Will these performance upgrades matter to the new software updates? Will having the pcm reflashed improve the slugish shifting points, or should I get a performance reflash from pcmforless.com? Thanks

[rodeo02]

If you want to go that route, the outfits that modify PCM's will program it suit your taste for shift feel.

Joel

[fortcarp]

Yeah I've heard that chips from jet & hypertech aren't worth much in performance gains, that the "specialty" company chips are much better. My real question I guess is will they incorporate the GM software updates along with firmer shifts? Or will the dealership be better to acheive this?

[rodeo02]

There's no incorporating GM software once you have your PCM reprogrammed by an aftermarket source. One reflash by a GM dealership and you are back to OEM specs. There's no "chips" to swap out. Only software to mod.

Joel

[fortcarp]

I see, thanks for clearing that up. I think I'll hold off on that. Just change tranny fluid and filter, see if those spongy shifts get better. If I knew what I was doing I would consider dropping valve body and installing a transgo shift kit. I did that once on a duster and the check balls fell out all over my garage floor!! I didn't know where they back in! I ended up taking the valve body with check balls in hand to a tranny shop, they put them back for me. Not wanting to go that deep into this one. Any recommendations once new fluid is in? Thanks
Carp

[rodeo02]

I hear you on messing with the valve body. I've never messed with one myself. I used a case of Napa Premium Performance Merc/DexIII universal ATF when I did a cooler line pumpout and dipstick tube refill on my 2005. Have about 8Kmi on that ATF (28K on truck) without issue. Mine does shift pretty firmly, especially into 2nd. Always did. Shift points and accelleration can feel like the bottom fell out if you are flogging the truck hard, but most of that is due to the software, or torque management as GM calls it. Basically it's there to keep the drivetrain from tearing itself up.

Joel

[fortcarp]

Cooler line pump out? Sounds easier than draining converter. Do these bellhousings have an access hole to the converter? I assume you still dropped the pan for the filter. What's the steps for doing it the way you did? I would like to get as much of the old fluid out as possible. Thanks
Carp

[rodeo02]

I believe there is a metal plug at the belly of the bellhousing, but AFAIK, there is no drain plug on the TC. To do a cooler line pumpout, crawl under and locate the steel line on the lower radiator tank to the right (pass side). That's the cooler feed line. These lines use a pain in the azz push lock setup. First pull back the black plastic protective collar ring. You then have to mash the line into the radiator and carefully pry out the circlip (with a fine pick) from the slot on the hex fitting in the rad. The line will pull right out once the clip is removed. Napa or the likes does sell the little plastic 'quick disconnect' removal bushings, but I couldn't get them to work for the life of me. I then shoved a 3/8" pc of clear vinyl tubing over the cooler line and routed it into an empty windshield washer fluid jug. A helper definately helps keep things steady. Start the truck and let the trans pump itself out. Once the ATF flow starts to sputter, shut it off. Be carefull as these 4L60E's will pump out a gallon of warm ATF in about 10sec! I tried it myself initially and made one hell of a mess, the hose blew out of the jug, whipped around... you know the rest. Basically, I pumped out a gallon, then added a gallon. I did this 3x and the system was all red and purdy! I'd like to drop the pan, do a magnet clean and add a drain plug to the pan around 30-36Kmi on mine.

Joel

[fortcarp]

I guess I'll drop the pan & clean the thing and install a new filter anyway. I'm sure it needs it at 57k. If I find a converter drain I'll let you know. Should be one if there is an access in bellhousing. Prolly have to bump starter a few times before it will point down. If not I'll have to do the line pump out like you did. I'd like to have a pan with drain in it too. The ones from like b&m or others are pretty pricey, but they do hold a few more qts. Thanks for info
Carp

[maxwedge]

No convertor drain on this truck.

[fortcarp]

That sux, so then to do a total drain with filter change I would have to drop pan, change filter, then do the line pump out like rodeo did? Does this hurt the tranny? The truck is running it's self outta fluid seems to me? That just seems like something will overheat, even if your fast at it. But if it works I'll give it a shot. I really would like to do this myself to ensure a quality job....you know? Thanks
Carp

[rodeo02]

I don't mean to take this thread off topic, but for an ATF pump out, using the transmission to pump itself out; yes, you wouldn't want to run the trans pump dry for long periods of time, but the only thing doing any work in a transmission that is in P or N, with the engine running is the gearotor pump driven by the input shaft. Nothing in the trans requires lubrication in those modes. You don't have to run it 'dry' anyway if you s/d the engine when ATF flow starts to sputter out of the cooler line. If you are not comfortable with the 'sputter' method, just pump out 2qts, s/d the engine, add 2qts, repeat, etc. You will always have some product mixing no matter what you do. There is NO WAY to get all the old ATF out of a trans aside from totally disassembling it and parts washing it.

Joel

[fortcarp]

OK, I'll drop pan for a filter change, then line pump out. Thanks for all your info, you know alot about these trucks. Haven't had mine that long and just starting all the major maintenance. I think mine had a hard previous life...nothing has been changed, runs good tho, trying to keep it that way.
Carp

[ScarabEpic22]

Dont bother with a dealer reflash, it will just update your OS to the most current one and still leave you wanting more. Basically you should get a PCM tune from pcmforless.com, I have their tune and it is awesome. Also I have a Magnaflow dual catback and a K&N FPIK2 57 Series CAI, these coupled with the tune makes for a pretty quick I6. I beat up on lots of rides, lots of sedans and take out ricers with ease while still giving SUVs my taillights.

[fortcarp]

Thanks for info, I have been leaning toward the tune if you have read the rest of my threads. I really hate the torque management on these. I want the Wester's tune, but damn $500 !!(?) How much was the pcm 4 less tune? Would you advise keeping my stock pcm & eating the core charge? That seems to be good insurance....just in case. You never know, I have read on other forums where the burns weren't perfect & some things were jacked up, customer sent in old pcm for core & was stuck with down time until he got it (pcm) fixed. Thanks for all the info