Chevy Express 3500 van struggles while towing
 

Hey all,
I picked up a 2006 Chevy Express 3500 to tow my family of 6 kids and our 4500# travel trailer.

It really seems to struggle, even in tow haul mode. Went to Colorado from Chicago and it really struggled going up a 6 degree inclines...max 25mph. Going down hills with a bit of wind requires apply decent gas. If we've done some heavy driving, it feels like I don't get much more power out of hitting the gas...just forces it to shift.

Is this all expected? I thought I'd get easier pulls. I've considered getting it tuned, if nothing else to see if they timings and such are correct.

Thanks!

What engine and what rear end gear ratio?

My 2013 savana has the 5.3 and 3.42 rear end. It pulls our boat, family and gear up the pass as if its not there.....my boat is not 4500 lbs, but still.

I have not towed, but if I put my foot down this thing moves. I'm not sure what components you have, but I just learned of the self-learning transmission a few weeks ago. It adapts and performs according to your current driving style. Up here where I am currently driving, it keeps me in lower gears and higher rpms. Saves my brakes and gives me more control.

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I see now that won't have my transmission, but you might have the 6.0.

The van is a 6.0L V8...I think that is all that was produced for 3500 Express extended passenger van.

I don't know the rear differential specs.

You can find out the specs of your van by running the VIN decoder at the top of the page, under "Tools".

But it may have to do with altitude, and I don't know if an '06 has enough smarts to compensate. I rented a car in Denver to go up to Breckenridge. It did okay in Denver(Mile High City), but as I went higher (about 11,000 feet) it would barely get to speed, and I wasn't towing anything.

4.8 would struggle but a 6.0 should pull that no problem even with 3.73. Does it pull ok empty? If not, cats clogged, fuel pump weak or the tc stator broken?

I'll look at the spec tomorrow.

Any idea if getting the car performance tuned might give insight or help?

Any vehicle with a MAF can compensate for thin air. That's going pretty far back. At least 90's.

mmj means map. map sensor recalculates for altitude at every key on engine off and at each wide open throttle. So if you drove from sea level up to Everest with shutting off the engine or a wot...it would not compensate.

Interesting ! so if I got this right , if you drive to the top of the 5000 ft Interstate pass , stop for lunch and then drive down the hill back to near sea level ( Bakersfield) the computer will keep the 5000 ft setting until you turn it off or go full throttle ?

is that how it works ?

Thanks for the info