Higher mileage '07 or lower mileage '04/05?

I have to admit, it's the AFM that has me looking towards the '07 and newer but the reality is I can only afford an '07 if I find a great deal on one. Looking at one tomorrow with 260k on it (600km commuter) but it's got the Service Suspension and Airbag messages displayed at the moment. I'd kinda rather hop in and drive for a while but am not scared of the messages and have read up on here and other sites what they may be all about. I'm bringing a licensed mechanic with me tomorrow to look it over. There are other things the '07's bring to the table that I appreciate too, like climate controls, updated interior design, current model parts and accessory availability etc.

I guess the question is the fuel economy really....I spoke with a guy that has an '07 for sale and he said that even with the AFM they were never really able to best the fuel economy of the pre-'07's with normal driving. Is this something this community has noticed as well? If it is I figure I might as well avoid the AFM lifter issue potential altogether and just look pre '07.

When this all began the AV was a short-term fix to a dying Trailblazer. I had my heart set on an '07 or newer Tahoe. Truth is, it seems that the AV is a better fit for my life and hobbies and family so I'm looking a little more long-term at this now.

Thanks in advance for any words of wisdom. Glad I found this forum!

I have a first gen truck, so I have no direct experience with the AFM, but there have been quite a few posts in this forum discussing problems associated with the AFM in mostly the '07 and some '08 trucks.

Personally, I intend to totally avoid purchasing any 07-08 just on account of the issues I have read about here.

There appears to be the potential for some serious engine damage due to the poor design of that system in those years.

Later models appear to benefit from some changes in the design.

Since the truck you are looking at is presenting a Service Suspension error in the DIC, you most likely have either one or more blown air bags in the rear air shocks and/or a burned out air compressor for those shocks.

Not an uncommon problem once these trucks get a bunch of miles on them.

I bought my truck with 116,000 miles on it and the blown shocks looked like they had been blown out for quite some time.

I don't think a previous owner of my truck was interested in replacing those very expensive OEM parts.

But I found and installed some aftermarket units and I have been very pleased with those parts for over 75,000 miles now.

I replaced both shocks and air compressor over four years ago and the problem was solved.

Get the actual code read for the air bag system error.

Cheap scanners often do not read ABS codes, so don't be surprised if a basic code scanner or one at an auto parts store give you no codes for the ABS error.

That may be something as simple as a bad sensor, but the codes should point you in the right direction.

Good luck with your new truck.

Personally, I'd go with the lower mileage 04/05.  Read up on the issues with the early years of AFM.  A lot of people deactivated the AFM to save their engines.  

That is a hard choice be careful with those codes, if  that service suspension turns out to be a stabitrac light I'd walk away.

Thanks for the insight. I'm going to capitalize on the mechanic coming with me and have him show me what to look for on the other units I look at without him. I think I've decided on the 04/05, body cladding-free model. The downer is that there are a few in town here but at "little lot" dealers. Not a fan of those places because I had a buddy work at one and tell me the "smart" things they did to shine up turds. Not saying they're all resourceful like that but still....I like to know human history if I can.

The mechanic is brining his scanner. Hopefully it's a better one than mine and can get to the bottom of the codes. Will the Stabilitrac code show on an over the counter scanner? Are there codes to run screaming from?

Dude selling it said, "I marked the price down from $15k to $8k just to be done with it and let the new owner take care of it." That should have been my clue. It'll be the miracle of miracles if it checks out ok.

And it's pewter. Never been a fan of pewter......sorry to those that do indeed like pewter - no offence intended.

I'm just saying from experience here. I'm not sure what scanner your guy has. Turn around and walk away if it's stabitrac

Totally agree with MS03 2500 concerning the Stabilitrak.

I am assuming we are talking about an LTZ with the rear air shock system.

If that is the case, one quick test would be one the very first attempt to start the truck, turn the key and start the truck then immediately step out and listen for the air pump located in the rear of the driver's side rear wheel well.

The air pump can be seen by looking on the frame rail through the wheel well and right behind the driver's side rear tire.

The pump should start and run for a few seconds at vehicle start up as a system check.

You will be able to hear it.

If the pump never starts up, the air pump may be burned out.

This happens and it will not hurt to drive the truck like that until you can have the system replaced.

The auto leveling system will just not function, but the truck can be safely driven just fine.

Also, have a look at the air shocks themselves.

Here is a pic of mine.


Now, mine were in really bad shape since the previous owner obviously had no desire to fix them and they had been blown out for quite some time.

The shocks in the truck you are looking at may just have a leak or a bad air hose and may not look this bad but still may not hold air.

I would not pass on a truck just because an air pump was burned out or the air shocks were blown out.

If your scanner can read the ABS codes and it shows a bad sensor, that is fairly easy to replace, as well.

My concern is with the engine.

If this engine shows misfire codes, especially for cylinder #7, then that is a reason for concern since it appears that cylinder is often the one that shows up when there is a problem with the AFM system.

The spark plug will often get oil fouled and the engine will begin to misfire.

But the oil fouled plug is often the least of the troubles with that engine.

I would move on to another truck prospect if that is the case.

Good hunting!

Update needed!

07 better front end