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About to buy a 2004 GMC Sierra Z71


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Posted

Hello,

I have been looking for a replacement for my tired Ford truck and I think I may have found it. I saw a 2004 GMC 4x4 Z/71 - OffRoad SLE extended cab truck for sale this past Sunday. It was parked with a sale sign on it in our local supermarket parking lot. Looked like new and has 41k on it. I called the guy and it sounds like a nice truck at a good price. He had to leave town this week but will be back Saturday to let me examine it closer and take it for a test drive. He said it has the 3.5 engine and 4 speed automatic transmission in it along with a factory tow package. Thats about all I know about it till he gets back and I can look at it again. I would lilke to know what the 2004 factory tow package included and what ratio gears this truck would have ? I assume the OffRoad suspension package would offer a standard 3.73 gear set along with positraction ? right ? If not, is there a tag on the differential that I can check to determine what the ratio is ? if so, how can I tell what the ratio is from the code ? I need the truck for occasional towing and usually tow a car hauler with a antique truck, total weight is about 5500 pounds. From the archives, it appears that if this truck has the 3.5 engine and 3.73 gears, it should be able to haul 6800 pounds.

Thanks in advance for your help !

Bill

Posted

personally, i would HAVE to have at least the 4.8l v8. i have the 5.3l vortech and tow 4500-5000lbs about 7-10 times a year and can't imagine anything less.

Posted

I'd have to assume you mean the 5.3V8 as there is no 3.5L engine offered. The least you could have would be the 4.3V6. As for a gear setup, you're likely looking at the G80, which would be a 3.73 locking rear end.

Posted

For 2004 model, the Z71 package included the locking G80 rear differential, fog lights, heavy duty shocks, skid plates, and Autotrac transfer case in the crew cab model, possibly also in the extended cab(not sure about that). The standard gears were 3.73, optional 4.10.

 

This was the last Z71 model with 4 wheel disc brakes. Most of these trucks came with a factory tow package, which would enable towing up to about 7900 lbs. Realistically however, you should not tow more than about 6K lbs with this truck, especially longer distances, and always use the tow mode! (refer to my "Another 4L60 transmission bites the dust" thread for more information).

 

The factory tow package includes the transmission oil cooler, frame mounted receiver hitch, and trailer wiring harness with a 7 pin socket mounted on the hitch itself, and an electric brake controller pigtail (no brake controller though). You'll need a 7 pin to 4 pin adapter for a typical flat 4 pin trailer plug.

Posted

Hello,

Yes, sorry, I meant 5.3 not 3.5. I currently use a 99 4x4 Ford Ranger with a 4.0 L engine with the OffRoad suspension package wich includes 4.10 (4.11?) gears which is rated to pull about 5500 - 5700 pounds. With extra over load springs in the rear, ultra heavy duty shocks all around, 2 inline tranny coolers and temp gauge along with electric brakes on the trailer, it does a very decent job of towing for a small truck. It's fine for occasional short trips that are less than a days drive but not something I want to drive on an extended trip or in montainous terrain. I think a light duty full size truck like this one will be fine for my occasional towing needs. Thanks to everyone who answered my questions. The answers are exactly what I hoped they would be. If the test drive is positive this weekend, I will probably go ahead and buy it.

 

Thanks,

Bill

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