QuestionQUESTION: Hi - i have a 04 Chevy Venture Van with 65K miles. I use it a few times a month to carry a lot of books (about 40 -50 boxes, seats are out, average size beer case boxes). I am wondering if I should replace the shocks, and should I get heavy duty shocks? When I am driving on the highway with a large load I can sense a difference in the handling. It bounces a little bit and seems hard to steer.
ANSWER: When I was in college I worked for a moving and storage place in the summers. Mostly they hired me 'cause I could drive stick and lift anything, but I took the time to learn a few things. When you buy cartons to pack things in for moving, they come in several sizes. The idea is that each carton should weight about the same. Guess what the smallest carton was called? That's right, a book carton. Books and newspapers (also did that, filling boxes at night, one summer) are the heaviest thing there is. I would rather deal with engines bolted to wooden pallets or drums of oil than fight with heavy cartons of books (a book carton is smaller than a case of beer, by the way). The Chevy Venture was no way designed to carry loads like that, especially since the drive is to the front wheels. I hate to think what is going to happen if you have to panic stop; I'm sure that the anti-lock brakes aren't going to be able compensate for that big weight in the back when it all tries to move forward. That said, there are two good solutions to your problem. If you are only doing this two or three times a month, you could get air shocks for the rear wheels. They take the place of your regular shocks, and can be pumped up with air to maintain your normal ride height. Then you could let some of the air out when you're not carrying the books. Problem is, you have to fiddle with them every time you change the load, which you'll get tired of doing, and they can leak, leaving you back where you were only poorer. If it was me, here's what I'd do: First, buy a stiffer set of springs for the rear. Moog makes a heavy duty spring intended for exactly your situation. It's part # CC695, and you can buy them through almost any parts distributor. At the same time, I would replace the rear anti-sway bar with a bigger one, to compensate for the increased rearward weight bias. ADDCO makes one, a part #2075. I have used ADDCO bars for years (too many years) on all sorts of cars and trucks. The manufacturers set up most vehicles to understeer, 'cause it's safer. The thicker rear bar will bring the handling back to the more desirable neutral characteristic. Take my word for it, they really work, you'll be amazed. You'll want to get a pro to install the springs (not difficult but dangerous if not handled properly). While you're at it, get him to do the rear anti-sway bar and give the car a good four-corners wheel alignment after he's done. Tell him what you carry so he can adjust for the load or, better yet, get the job done with the books already in the car so he can set it up right. You'll be happy and a whole lot safer. Oh, and I hope you are using a tire with an appropriate load rating, not something cheap from Pep Boys. Wouldn't hurt to slip by the truck stop sometime when you're hauling and get a weight to compare to the empty weight. You'll be surprised at how much those books really weigh.
---------- FOLLOW-UP ----------
QUESTION: THanks for your very knowledgeable answer. Is it possible I will do, or have done, any damage to the van? I really only carry a very heavy load about 4 times a year, and it is not for a long distance (40 miles or so).
If you could settle a dispute between me and my husband, he always says to put the heaviest items right behind the front seats, I feel it is better to put them over the rear axle.
Also, my traction control system is not working, I have checked all the fuses but don't know what else to do. The last time it quit it was just a fuse.
Answer You may have damaged the rear shocks. But not necessarily. If you only do this four times a year, then I would not advocate changing the rear springs. The new anti-sway bar would still improve handling under all conditions (you'd really be surprised). What I would advocate is that you make these heavily-loaded trips at low speed. No more than 25 on the surface streets and no more than 40-45 on the highway (and try not to use the highway). Inertia increases with the square of the velocity; at 50 your van has four times the kinetic energy as it does at 25. This is what makes it seem unmanageable (and it actually is, a little) when you are driving it loaded. Traction control is a function of the anti-lock brake system, I would suspect a speed sensor on one of the front wheels might be bad. It really should be hooked to a diagnostic computer to determine the exact cause.
