Hey guys, this is going to be a long post, sorry. Just want to add a bunch of data points to this thread.
2014 Chevy Express 1500 AWD Cargo
Interior is built out pretty much just the way we want it.
Exterior has solar panels on the roof, 2 Thule cargo boxes, MaxxFan roof vent.
Van is currently lifted ~3" in the front, ~4" in the rear. Initially I cranked the front all the way up and got 4" lift in front, but the ride was too bouncy, so I backed it down.
It seems the lift and tires are the most desired information, so I'll summarize our setup in this post.
First, regarding MPG: I've kept a detailed gas log since new (9 miles on the clock), it has 42,6XX now.
The best we saw was when the van had ~3000 miles, stock everything, nothing on the roof, not much inside, OEM tires. We reached 19MPG. Mostly highway driving.
The worst we have seen is randomly, when mostly city driving, winter driving, van fully loaded, with lift and A/T tires. We got 13.5MPG.
For the last 6 months or so, we've seen a pretty consistant milage. Doesn't matter much what style driving, van load has been pretty constant, with lift and A/T tires. We get 15MPG.
Our milage has dropped because of 2 things: The stuff on the roof and the tires. The lift had no effect on MPG (lift and tires happened separately)
Second, we are running stock size 245/70R17 Cooper Discoverer AT3 tires. They are a HUGE improvement vs. OEM, but did bring down our fuel consumption by 1MPG and are louder. Not anoyingly loud, just noticable (and expected).
Okay, our lift:
Here's how she looked before the lift:
Here's how she looks right now (4" lift rear, 3" lift front):
Here's a picture of all the parts that went into this except for Longer leaf spring U-bolts:
Here's a picture of the longer U-bolts and flip kit:
Here's a picture of the new and old leaf spring next to each other:
Complete Parts list:
Suspension Maxx Cam 3" Front Torsion Bar Key Leveling Lift Kit 4X4 4WD SMX-MC2 - $224 (ebay)
GM Chevy Ford Dodge Torsion Bar Unloading Tool - $26 (ebay)
22-907 1992 - 1999 Chevy Suburban rear leaf springs, 2900 lbs capacity, 6(5/1) leaves - $380 w/shipping (generalspringkc)
(U8020) U-bolt reversal, 1/2 ton - $87 w/shipping (offroaddesign)
2 pair of Energy Suspension 9.9132G Ultra Low Bump Stop (keep springs from slapping) - $26 (amazon)
2 of Bilstein (24-186643) 5100 Series Shock Absorber (front shocks) - $150 (amazon)
2 of Bilstein (24-221948) 46mm Monotube Shock Absorber (rear shocks) - $184 (amazon)
Total Cost: $1077
Initially I didn't think I'd need new U-Bolts, but the nuts were right at the very end of the bolts. No threads exposed. The spring pack provides 1 7/8" lift just due to it's thickness. So I got longer bolts and decided to flip them as well, help the axle clearance a fraction.
The brake lines in the rear are JUST BARELY long enough at full droop. There is a clip in the frame that holds the slack when using stock springs, I had to remove that clip with the taller springs.
EDIT: The U-Bolts I got were a tiny bit long, I was worried that if the spring compressed much, the tops of the bolts would smash into the body. I hack-sawed the U-Bolts after installing, probably cut off 1 inch, still have maybe 3/4 inch of thread beyond the nuts.
My impressions:
Stock, the van sucks. It has like 3 inches of clearance. On a few occasions I scraped the front crossmember and the exhaust on the mildest of terrain. The trailer hitch would scrape exiting driveways. The rear end was really sloppy, way too soft. Loaded up, it would bounce and hit the bump stops in the rear going over speed bumps at a crawl.
I highly reccomend new rear leaf springs. Putting blocks under the stock sponges didn't seem like it would help much to me. The ride now is very truck-like. Firm, but not bouncy, not spleen-killing. (It was bouncy and spleen-killing with the front cranked to 4").
We've had the lift on for about 1.5 years now. It has not effected fuel milage (only the A/T tires did).
NOTE: The front shocks are gas charged. I got them thinking it would help lift the van a tiny bit. Maybe they do? HOWEVER, I suspect that if I didn't get the gas charged, the ride while cranked all the way up would have been better, not bouncy.
Wear and Tear on components:
After 1.5 years and ~15,000 miles, everything seems to be working just fine. BUT, I have started to notice a very faint, sporadic squeal from the front end. I suspect either a wheel bearing or CV joint. It is so faint my wife can not ever hear it (thinks I'm crazy) and I can't figure out if it's driver/passenger side. It will have to get much worse before I can locate it.
Recently (in the past month) the passenger side front axle seal has started leaking. I just noticed this yesterday. I don't believe this is related to the lift in any way. From what I can find, this front axle is also used in GM AWD/4WD SUVs/Trucks, and they are notorious for leaky axle seals, even at 40k miles. I've read that the dealer will fix it for ~$300-350 (unless they do it under warrenty, even though it expired at 36k miles). I intend to find out.
Picture of leaking axle:
Legend:
Red = CV / Axle mating
Green = Axle tube flange, where axle exits tube, where oil is coming from
Blue = Oil splatters
Pink = Axle tube / differential mating, also where the axle seal is located
Lastly, a cautionary note:
Last night there was a semi tire or plastic wheel well liner on the highway. Couldn't see it until too late, ran right over it at 50MPH (driver side). Immediately the entire dash lit up with Stabilitrack/Traction Control/AWD/ABS/Check Engine Lights. Came to a stop a few seconds later, tried to turn off the highway, and the motor shut down. Would not restart. Acted as if it had no fuel. Eventually found the problem, the (what I assume to be) traction control computer is located on the driver side exterior frame rail just in front of the back tire. It got whacked by the object, the plug has a plastic door on it.
That got ripped open, and apparently that SHUTS DOWN THE WHOLE VEHICLE. The door closes some circuit. I closed it (now half broken) and everything works fine, started right up. (Still have check engine light on, but I suspect when I pull the code, it will be "lost comms with ECU" or something).
The location of this computer is, in my opinion, the worst and most exposed place for something that will DISABLE YOUR VEHICLE if struck. Had we not been stopped, we would have lost power steering and power brakes (maybe even AIR BAGS?? Sound familiar, Chevy??).
So just beware, and be careful of objects or rocks that might come near that thing. I'm thinking about moving it or welding a steel cage around it.
Picture of computer:
I have a bunch of pictures from doing the install, but have to locate them. So I can potentially provide pictures on request of specific things.
Feel free to ask about anything I forgot.
Cheers!
