# What to look for in an 04 m6. Potential buyer



## Cwarta (Oct 26, 2011)

Im looking at buying an 04 m6 gto, silver. All stock, never touched by a kid. An 65 y/o man owns it, met with him and we talked about the car. Obviouslyy you all already know its a 5.7 6 speed. The car has 56,000 m.i on it. What do you all think its worth. I would be the second owner. They want $15,000 for it


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## 2004goat (Feb 10, 2010)

it sounds pretty good. But maybe i would try and do it for $13,500


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## Cwarta (Oct 26, 2011)

Ok thanks, im trading my 05 rx8 shinka in on it. I drove the car and was like wow, this things got some cahonas. Very slick car. I used the search function also guys and couldnt really find what i wanted.... Im mainly looking for comon issues associated with the hotroding/abuse to look for in this used car. thanks for your help!!


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## ViperT4 (Jul 18, 2010)

Definitely would not pay more than $13,000 for an 04 with that many miles. I paid $13,000 for my 04 M6 with 43,000 miles and already had a K&N and cat-back on it. Where are you located?


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## Cwarta (Oct 26, 2011)

In Nebraska. I have always wanted a GTO, but but couldnt afford one. I just want to get rid of this POS mazda that is falling apart @65,000 mi and if i can get myself into this GTO i will be ecstatic. I get 19mpg with this mazda highway. Hoping to get around 22-23 with the gto.


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## jpalamar (Jul 22, 2008)

Check out the first 2 pages of each tech section. You will see common threads of what fails.


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## HP11 (Apr 11, 2009)

Cwarta said:


> I get 19mpg with this mazda highway. Hoping to get around 22-23 with the gto.


I guess it can be done but, coming from a RX8, you'll have to alter your driving style a bit.


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## Cwarta (Oct 26, 2011)

What is common milage with an m6? its rated 29 on the e-net, obviously i didnt believe that. But is it easy to pull 23+?


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## ViperT4 (Jul 18, 2010)

I think the LS2s get better mileage. With probably 80% highway driving I get 19.5mpg total average. Honestly I think that's pretty good for a 400+ hp car with the conservative (relatively) mods I have.


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## Cwarta (Oct 26, 2011)

Im going to have to make it atleast equall the milage of the rx8 to atleast make the pl lady happy. It could pull 21 on a good, GOOD day. IS it doable?


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## ViperT4 (Jul 18, 2010)

Don't RX-8s get real $hitty gas mileage anyway? You'll do better than the Wankel and the LS1 is a more reliable and will last you twice as long.



Cwarta said:


> Im mainly looking for comon issues associated with the hotroding/abuse to look for in this used car. thanks for your help!!


Effects of hot rodding are no different in the goat than any other. Look for signs of water or coolant in the oil. Rough shifting or noisy rear end would be bad. If there's lots of rubber coating the rear bumper behind the wheel well you know the guy did a lot of burn outs.

For regular wear and tear GTO specific problems look for strut rub, rear end sagging because the springs are shot, cracked and dried radius rod bushings up front. Find out the stock ride height and measure if the rear is more than 10-15 mm off from that. For the rr bushings drive at about 10-15 mph and have a buddy watch from outside. Stand on the brakes and if the body keeps going forward a good deal, even so much as to make contact with the backs of the front tires, the rr bushings are shot which is common. Strut mounts are probably in need of replacing by now as well, but i don't think that deteriorates the ride or safety at all. I could go on...


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## HP11 (Apr 11, 2009)

ViperT4 said:


> I think the LS2s get better mileage. With probably 80% highway driving I get 19.5mpg total average. Honestly I think that's pretty good for a 400+ hp car with the conservative (relatively) mods I have.


I've always seen the EPA estimates as 16/26 for the 04, 17/25 for the 05 (directly from the monroney sticker for my car), and 17/25 (from the 2006 showroom brochure) all for manual trans. Pretty close to the same, for whatever that's worth. I generally average about 16.5 or lower but I don't drive with an eye toward fuel economy.


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## ViperT4 (Jul 18, 2010)

HP11 said:


> I've always seen the EPA estimates as 16/26 for the 04, 17/25 for the 05 (directly from the monroney sticker for my car), and 17/25 (from the 2006 showroom brochure) all for manual trans. Pretty close to the same, for whatever that's worth. I generally average about 16.5 or lower but I don't drive with an eye toward fuel economy.


I could swear on my unconceived children's lives that LS2s get better actual highway gas mileage because they have DoD so they're running on half the cylinders. Maybe they're just not quoted that way tho


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## jpalamar (Jul 22, 2008)

04 will get better highway MPGs because of lean cruise.


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## Cwarta (Oct 26, 2011)

Well i own a 600 rwh 4x4 cummins i do nasty boosted launches with, a built 327 4 spd nova 1970. Im hopping i can just daily drive this without tearing it up, but i doubt it lol. I will get the bug, just like i did with my once stock cummins


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## HP11 (Apr 11, 2009)

ViperT4 said:


> I could swear on my unconceived children's lives that LS2s get better actual highway gas mileage because they have DoD so they're running on half the cylinders. Maybe they're just not quoted that way tho


That's the 'lean cruise' as jpalamar mentioned. From what I understand the lean cruise is not enabled in the U.S. cars and has to be 'turned on' through a tune. So it wouldn't be included in the U.S. fuel economy figures. Oh, and I think you mean unborn children. Hopefully they won't concieve until they're old enough.


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## ViperT4 (Jul 18, 2010)

But lean cruise as you're calling it wasn't on the 04s, so why would they get better hwy mileage? Displacement on Demand, on the other hand, definitely was introduced on LS2 and variant powered vehicles starting in 2005.

And I do mean unborn children, but don't even have any cooking yet and didn't want to give anyone any ideas so I went with conceived. Either way...


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## Cwarta (Oct 26, 2011)

I have a diablo sport trinity that i run on my cummins. It will also work on the gto. Can i possible pick up any mileage on the gto with that? even just 1mpg would be great. This car will be my wifes daily driver and my weekend bruiser prolly.


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## HP11 (Apr 11, 2009)

The lean cruise was on the 04s only; just not enabled in the U.S. I've actually never heard of the 05-06 GTO's having displacement on demand; from what I understand; the oilways are present in the GTOs version of the LS2 for the solenoid valves and hydraulic followers but the system was never installed on these cars. The only Pontiacs that had it, as far as I know, was the G8 GT with the L76 engine.


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## jpalamar (Jul 22, 2008)

The GTOs don't have any displacement on demand. The LS2 is always on and ready to go vrrooom!


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## HP11 (Apr 11, 2009)

I have an LS2 out of a Traiblazer SS out in the shed on a stand that I'm setting up for a future project. It's a slightly detuned version (only slightly - 390 hp vs. 400 hp). When I had it apart it also looks like it was set up for dod but the valves and followers aren't in that version of the engine either.


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## Cwarta (Oct 26, 2011)

I have a diablo sport trinity that i run on my cummins. It will also work on the gto. Can i possible pick up any mileage on the gto with that? even just 1mpg would be great. This car will be my wifes daily driver and my weekend bruiser prolly.


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## Gotagoat (Jan 6, 2006)

My LS2 M6 averages about 17/22 with moderate driving. Occasionally running up between 3000-4000, my average shift point around 2300. Only mods are a shift delete and Afterburner catback. I believe that if you never ran it up above 2500, you could improve the mpg to 19/24 (perhaps more on the hwy if cruising the speed limit). So if your wife is really easy on the gas, she may get the high numbers and on weekends, you could do whatever. You'll both be happy with the car.


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## HP11 (Apr 11, 2009)

Cwarta said:


> I have a diablo sport trinity that i run on my cummins. It will also work on the gto. Can i possible pick up any mileage on the gto with that? even just 1mpg would be great. This car will be my wifes daily driver and my weekend bruiser prolly.


Not sure if you can turn on 'lean cruise' with a handheld or if you'd need a Tech 2 for that. I'm not familiar with them. What things are you able to view with a Diablo Sport Trinity?


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## ViperT4 (Jul 18, 2010)

Cwarta said:


> I have a diablo sport trinity that i run on my cummins. It will also work on the gto. Can i possible pick up any mileage on the gto with that? even just 1mpg would be great. This car will be my wifes daily driver and my weekend bruiser prolly.


Yes, if you can access your fuel trims you can decrease how much fuel you use. I've read that the goats run rich from the factory so there should be some room to play with, but only on the internetz so don't come after me if you do it and melt your engine.  If someone knows I'm wrong from experience please correct me.


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## Cwarta (Oct 26, 2011)

Im not sure what i can view as i have not hooked it up yet. Im hoping to bring home the car tonight. I know on my cummins i have 4 different guage pages (5 guages per page) i can monitor.


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## The_Madcat (Sep 30, 2011)

Doesn't DoD require special lifters and or solenoids to work correctly? Not overly familiar with it, more familiar with the Mopar equivalent.


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## HP11 (Apr 11, 2009)

The_Madcat said:


> Doesn't DoD require special lifters and or solenoids to work correctly? Not overly familiar with it, more familiar with the Mopar equivalent.


Yes, that is what I was alluding to in posts #19 & #21. Or, more accurately, the fact that they're not there but then engine is designed to accomodate them.


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## Cwarta (Oct 26, 2011)

Update on the car. I am going to get the GTO. I fell inlove with it the moment my a$$ touched the seat. Im giving them 14,000 for it. It looks so tame and inoccent untill you hit that and comes to life. Should be picking it up tomorrow. Thanks for all the great info! Ill be frequenting on here alot lol


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## Cwarta (Oct 26, 2011)

Well i got my car today, all i v\can say is wow. This car is phonomenal. Im in love with it. What is the top speed on these cars, as i got to 130 and got scarred lmao


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## Cwarta (Oct 26, 2011)

She`s got 56,000 on her


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## ViperT4 (Jul 18, 2010)

Cwarta said:


> Well i got my car today, all i v\can say is wow. This car is phonomenal. Im in love with it. What is the top speed on these cars, as i got to 130 and got scarred lmao


Only ridiculous speed since it's an 04. The LS2s make it all the way up to ludicrous speed.

Congratulations on the buy, and BE SAFE. There's enough wrecked goats out there already.


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## Cwarta (Oct 26, 2011)

Thank you! Im madly in love. I cant see how anyone would sell one lol!!!


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## Littleguy (Jul 3, 2011)

Congratulations! I feel the same way about mine.


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## HP11 (Apr 11, 2009)

Littleguy said:


> Congratulations! I feel the same way about mine.


Sounds like you need to update your signature.......


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## Cwarta (Oct 26, 2011)

Speaking of whitch, i filled in the signature information and it wont show up? If you put to much in could it cause this? I also put in my profile picture but its not showing up either!!!


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## 646904GTO (Feb 10, 2008)

Good buy. I get 19 combo and drive it like I stole it everyday. I get a solid 27 mpg hwy at average 70 mph. So if you drive 60-65 it will go up 1-2 mpg better on the hwy. From what I understand all the 04 GTO had the lean cruise in the ECM. I used a Predator Diablo and adjusted my LTFT's to 0.0% by dropping my injector pulse by 7%. '06monteSS' has a thread about this. Yes I love my car. After I bought it the seats were so comfortable that I got rid of the racing seats in my '64 GTO Roadracer and bought a set from a wrecked car and fabbed them into it. I did upgrade my rotors with drilled and slotted ones and some really good pads, good money spent. Enjoy your car.
You will need to got LS1GTO.com to find the fuel trim info from 06montess.


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## 646904GTO (Feb 10, 2008)

Cwarta said:


> Speaking of whitch, i filled in the signature information and it wont show up? If you put to much in could it cause this? I also put in my profile picture but its not showing up either!!!


I think it goes through an 'approval' process first.


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## Cwarta (Oct 26, 2011)

^^^^^^^^
Hey thanks !!!


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