Towing/Trailer Hitch
The factory Astro/Safari van hitch is what I would call a class 3 hitch, refer to your owners manual. For aftermarket hitches, you must find the label or identify the exact model of hitch to get the rating. If the hitch has a 2" receiver, it 'should' be a class 3 hitch, but I wouldn't trust that, you should ensure that it's rated for whatever you plan to tow. If you tow regularly consider adding an auxiliary transmission cooler to prevent your transmission from overheating.
If you don't have a users/owners manual, you can find a copy for most years here: User/Service Manuals and Docs
What about trailer lights and brake controllers?
See the TrailerWiring page for wiring, connectors, and brake controllers.
How much can I tow?
This is a very common question, and the answer depends on many factors, some are listed below. Make a list and fill in as many values as you can to determine what you can safely tow/haul.
Gross Vehicle Weight Rating(GVWR) Max your loaded vehicle can weight - Found on vehicle information sticker on drivers door, owners manual, or contact GM
Gross Combined Weight Rating(GCWR) Max weight of loaded vehicle and trailer combined - Found on vehicle information sticker on drivers door, owners manual, or contact GM
Maximum Trailer Weight - Max your loaded trailer can weigh when properly equipped/setup - Found in owners manual, or contact GM
Gross Axle Weight Rating(GAWR) Max weight allowed on each loaded vehicle axle - Found on vehicle information sticker on drivers door, owners manual, or contact GM
Tire weight rating and pressure Max weight rating of your tires, usually listed on the tire or available from the tire MFG - Some people put car tires instead of LT tires on their vans, always worth checking and keep your tires properly inflated
Axle Gear Ratio RPO sticker, see gear ratio list, or contact GM
Gross Trailer Weight(GTW) Actual measured weight of trailer including all cargo(water/waste/food/dishes/propane/clothing/etc)
Tire Weight Rating Found on tire sidewall
Hitch Receiver Rating Found on hitch or contact MFG
Hitch Ball Rating Found on hitch ball or contact MFG
Hitch Type Weight-carrying or Weight-Distributing(see below)
Trailer brakes Owners manuals state the towed trailer weight should not exceed 1,000lbs if the trailer does not have it's own braking system
Sway Control Most of the Astro/Safari owners manuals state that any trailer over 2000lbs should use a weight distribution hitch and sway control
Vehicle registration Some states have different registration weights, this is separate from your vehicle MFG GVWR listed on your title and is specified on your registration, this can affect your legal GVWR. Some register their vehicles for a lower weight if they are not going to be carrying a lot as it can affect the vehicle registration fees.
Other factors also affect your ability to tow:
Driver experience
Temperature/Weather
Vehicle condition
Terrain and Altitude
Road surface conditions
You have to use the lowest rating! Lets say your ball is rated at 7,000lbs, the hitch is rated at 6,000lbs with a weight distributing setup and the owners manual says that the vehicle can tow 5,500lbs with a weight distributing setup: The max you can tow is 5,500lbs with a WD setup.
Another example would be using an 04 AWD Passenger van with 3.42 gears, a typical class3 ball mount, trailer has it's own brakes and the hitch is a Weight Distribution(WD) setup: The hitch is rated at a max of 6,000lbs, the ball rating is 7,500lbs and the vehicle rating is a max of 4,600lbs. The max you should tow with this WD setup is 4,600lbs.
Using the same example in the most common Weight Carrying setup, the vehicle owners manual says that the max you should tow is 2,000lbs with a max tongue weight of 200lbs.
Hitches:
Before installing your hitch, it is wise to clean up the threads in the frame that will be used, using an tap for your bolt holes. I used an M10x1.5 tap like http://amzn.to/2tyLvvf (link only for reference, cheaper to buy at LAPS ~ $5) to chase the threads on my 2003.
Here are some hitches that fit our vans, I won't include the lightweight ones as I don't feel they are worth the money. Note: You can often find them used at your local junk yard. I bought mine there for $15-20 used quite a few years ago, it was like new. Personally I wouldn't buy anything other than a 2" receiver/hitch that is rated at the max towing capacity of the van. That way you are ready to go with any size load or accessory that the van can handle.
http://amzn.to/2FuVza2 (same as uhaul?)
http://amzn.to/2FGMQov (if you want more mounting options, but a lot more bolts to routinely check, I prefer welded hitches)
Lets look at an example trailer hitch, the Draw-Tite 75122:
Receiver opening: 2" x 2"
Rating: Class III
Do not exceed the lower of the MFR's vehicle rating or
Maximum gross trailer weight: 3,500 lbs(Weight Carrying(WC). This is a standard hitch, no weight distribution bars/chains setup.
Maximum GTW when used with weight distribution(WD): 6,000 lbs(this is a special setup, not the usual throw a ball on the back and tow setup)
Maximum tongue weight: 300 lbs(Weight Carrying(WC) This is a standard hitch, no weight distribution bars/chains setup.
Maximum Tongue Weight when used with weight distribution(WD): 600 lbs(this is a special setup, not the usual throw a ball on the back and tow setup)
"The trailer tongue weight (A) should be 10 percent to 15 percent of the total loaded trailer weight, up to a maximum of 200 lbs (92 kg) with a weight carrying hitch. The trailer tongue weight (A) should be 10 percent to 15 percent of the total loaded trailer weight, up to a maximum of 750 lbs (341 kg) with a weight distributing hitch." - 04 Owners Manual
Not having your load balanced and having the proper amount of weight on the tongue can severely affect towing performance. Easiest way to ensure is to use a scale, they even have some built into hitches that will give you the tongue weight like: https://amzn.to/2LB3P04
Safety Chains:
Safety chains are a requirement! They should be crossed under the trailer tongue so that it catches the tongue in case of a hitch ball failure with just enough slack to make turns and not drag on the ground. Some people twist them just a little if there is too much slack where they could hit the pavement.
Weight Carrying(AKA Dead-Weight) or Weight Distributing?
The standard way of hook up and go is a Weight Carrying(WC) setup. The problem with a weight carrying setup is that as more weight is put onto the hitch, it tends to unload the front of the vehicle, causing steering and braking issues(remember that your front two tires/wheels/brakes do most of the braking). While driving along a flat stretch of road this may not be apparent, however if you are on a decline or braking, the effect becomes greater.
You only have a Weight Distributing(WD) setup if you have something that looks like this mounted to your trailer/hitch: The benefit is that as the load on the hitch is increased(during braking for example), more of the weight is transferred to the front of the vehicle, helping you maintain proper braking and steering.
What about hitch extensions?
The MFG for a 12" extension states that the tongue weight capacity drops by 50% when you use their extension. Example: If your hitch states 500lbs allowable WC tongue weight, that becomes 250lbs when using the 12" extension.
What about a hitch mounted bike carrier/cargo box?
The MFG ratings above are for towing, not for a hitch mounted carrier. It would be completely safe to say, follow the vehicle MFG weight carrying ratings. Example: If your hitch and vehicle MFG states a 400lb WC tongue weight, don't exceed that for your box/carrier and included cargo.
However, I have personally gone above that limit for, lets say a 'few' miles. ;)
How much is too much? That is going to depend on your setup, upgrades like springs/bags/Timbrens could increase the capacity of your suspension to a point, though that does nothing about the braking nor the steering. However, if any of the following occur you are definitely overloaded:
If it's difficult to brake or steer properly, steering tends to feel 'light'
Headlights are pointing up
Rear end is sagging, like a dog dropping a deuce in the neighbors yard
Tigers and other RV conversions:
When the vehicle has been modified, you have to be extra careful when towing. For example, on the Astro/Safari based Tiger RVs Provan extended the bumper mount and the 2 inch bumper mounted receiver is only rated to carry the generator. If you try to carry more you are likely to crack the frame or lose your load completely. Not to mention that you should keep your Gross Vehicle Weight below the Gross Vehicle Weight Rating, and that includes the sum of the van, passengers, fuel, gear, propane, fresh water, waste water, and tongue weight. It is common for RVs conversions to already be at or over the original GVWR of the base vehicle before you start adding anything extra.
Can I tow an Astro/Safari van with a tow bar or tow dolly?
Of course you can, but you have to be smart about it. Using a car trailer is your best and safest bet, but not always an option(weight also comes into play, 5-600# tow dolly vs 2500+# trailer). Using a proper tow vehicle(heavier than what you are towing) and setup is extremely important. Simply putting the transmission in neutral does not make it OK to have driven wheels on the ground, you can ruin your transmission/transfer case.
Flat towing using a tow bar, remember to disconnect all driveshafts and have the steering unlocked. Remove the driveshaft(s) from the differential(s) and tie to the body, also don't forget to tape your u-joint caps on. Follow the tow bar instruction manual and all laws in your route of travel(including aux brakes and breakaway brakes)
Using a tow dolly with the front end on the dolly, remove the rear driveshaft. Remove the driveshaft from the differential touching the ground and tie to the van body. Follow the Tow Dolly instruction manual and all laws in your route of travel(including aux brakes and breakaway brakes)
If you are using a U-haul tow dolly, some of them are quite narrow(keeps people from towing trucks with them) and will require using the skinny spare tires up front.
Their computer system will tell you that the tow dolly is not compatible to tow an Astro/Safari van, however, if you tell them you are towing a small car like a Honda Civic, you can make it work.
Never leave cargo or people in the towed vehicle, never tow it backwards, and don't backup.
Trailer brakes/brake controllers:
The owners manuals say that anything over 1,000lbs needs to have it's own brakes, you also need to follow the laws everywhere on your route of travel. There are a few different types of trailer brakes but most commonly you have two types.
1. Hydraulic surge brakes - you find these on rentals a LOT as they don't need a brake controller. The simple act of the towing vehicle slowing down forces the master cylinder to apply pressure to the slave cylinders activating the trailer brakes. Be careful backing as that will also apply the brakes if you don't lock them out using the lockout lever/pin.
2. Electric brakes - most heavier home trailers have this type of braking system, it's more versatile when towing but requires a brake controller fitted to the vehicle and the proper matching connector for each trailer(or adapters).
Ball Sizes and Ratings:
Trailer hitch balls sizes are pretty well standardized in North America. However, the weight rating can vary greatly. The 1-7/8" balls are good for ~2000-3500lbs, most 2" balls vary from about 2,000lbs up to about 12,000lbs depending on the material and shank size. If you are outside of the USA or NA, please be careful as the metric balls are quite close in size but are generally NOT compatible. Use the proper size and rated trailer ball for your trailer/load/coupler.
It would be ideal IMO if they would ditch the 1-7/8 ball size all together and standardize on the 2" ball. I have done that on most of my trailers already with replacement 2" couplers. That way I only have to worry about 1 properly rated 2" ball for all of my towing needs.
Tow/Haul Button:
The tow/haul button on the column shifter of the 99 and up A/S vans must be activated manually, and after every restart if needed/desired. There is a light on the dash which indicates when it's active.
Tow/haul mode is recommended when GCWR is 75% or more than rating. With a lighter/no load there is no benefit, may be unpleasant and will increase fuel usage.
Especially useful when hauling a heavy trailer in stop and go traffic, hilly terrain, low speed, and parking lots.
Tow/haul mode reduces the number of throttle pedal changes needed while towing.
Tow/haul mode will decrease the number of upshifts and downshifts.
On closed throttle deceleration it will hold the current gear.
Tow/haul mode only affects shift points below 55mph, minimum shift increases by: 1-2 shift -8mph, 2-3 shift 15mph, 3-4 shift ~30mph.
ATV wheel chocks and straps:
I was looking at a better way to strap down my ATV when I found these. It's amazing how much the price can vary depending on where you buy them.
I am really glad I picked them up as it makes it literally a 2min job to strap down the ATV. As with anything you can also make your own similar setup using e-track and some straps. An additional benefit on this setup was that with the ATV loaded, I measured the trailer/tongue weight and now it sits perfectly every time without worry.
Erickson 09160 Wheel Chock Tie-Down Kit http://amzn.to/2pF45z4
Also branded as:
Moose: https://www.denniskirk.com/moose/wheel-chock-and-tie-down-strap-kit-09160.p4000808.prd/4000808.sku
Cabela's Tire Tite: http://www.cabelas.com/product/Cabelas-Tire-Tite-System/1978095.uts