how does the awd compared to the 4wd on sandy road or on sand dunes?
What kind of vehicle?
There are many different systems. Comparing them is difficult.
Which vehicle are you talking about?
What a wonderful question. That really is a melon scratcher. I bet if you put the number of wheels the car actually has (we will define wheels as those circular shaped thaings that actually touch the ground–i.e. don’t count the spare and count dually, tripplies, quadrupllies, etc as a single wheel) in the denominator and the number 4 in the numerator and the result is exactly 1, then we’ll call it an AWD, otherwise it isn’t. Mark this up with any comments you’ve got and then send it to the axiom committee for review.
Sand dunes? The biggest issues are floatation and weight distribution on the drivewheels. Perhaps the best dune buggys ever were made from old VW Beetles, and they were 2WD…without limited slip.
We have a variety of vehicles at work. I don’t know about sand but in snow the awd performs the same as 4wd. The gas mileage savings for the option of using 4wd when needed seems to be the biggest difference.
Sand differs as much as snow. A sandy road like a snow covered road, you can handle with speed, awd is the best with it’s center differential. If it’s deep and slow going (DUNES ?) and getting stuck is the issue, nothing beats the traditional part time 4wd systems you find in many trucks and truck based SUVs with no center differential but often has low range gearing.
Exception is the vehicle with both 4wd/awd with a center differential that can be locked. It serves both uses.
Do not drive part time 4wd fast as it creates handling problems at speed; which is the big difference in how each is used.
Each of these awd or 4wd labels is subject to a car makers interpretation…example is the awd system on a crv has 4wd plastered on the back. That makes me and everyone else confused. The crv technically has no center differential but has clutches in the read diff that makes it act that way.
I’m getting a head ache.
Driving on sand you want almost the opposite vehicle that’s good in snow…
When driving on snow you want to dig down into the snow to the hard packed snow or pavement…driving on sand you want to float on top.
We’ve had this discussion before and actually they are quite similar. It appears different because in the snow conditions we encounter you want to sink to the base to get traction as you stated, which requires a narrow, non floating tire. If the base is unreachable, very deep snow, like mud and sand, you need flotation. This is true in sand, mud or snow.
Check utube and 4wheeling in the Arctic where the base is unreachable and vehicle would get “hung up” otherwise. They use mud type flotation tires. Same as it applies to snow cats and their flotation tracks.
Exception is the vehicle with both 4wd/awd with a center differential that can be locked. It serves both uses.
Do not drive part time 4wd fast as it creates handling problems at speed; which is the big difference in how each is used.
If I understand correctly, I beg to differ. 03 Blazer with 4wd auto setting. The drive basically engages the front drive shaft and kicks in 4wd as necessary. It usually kicks in only at stop lights then disengages. The only time it kicked in other than at stoplights was passing a car going 10 mph pn a country road. The windrows were pretty sclick, and it was like driving a train on a track, solid, smooth and complete control.
Are we all getting a head ache trying to answer this one ? I don’t think there is a difference of opinion. The 03 either has a center diff or not and it engages automatically into an awd (center diff) like mode or 4wd with no center differential or not. There is no disagreement. Sounds like it’s truck based w/o a CD and only the transfer case is affected, cause it does it only at low speeds. Or if it has a CD, it has an automatic lock or what ever.
Even longer wind explanation here.
Check utube and 4wheeling in the Arctic where the base is unreachable and vehicle would get “hung up” otherwise.
I didn’t say you HAVE to get to the base…you do have to get to the hard pack though.
In some snow conditions you create your own hard pack with the narrow tires, but only if there is a base that allows it for the conditions your in. That’s no assurance that will happen in deep snow, mud and sand and then depending upon it’s density. When that happens, you need more flotation.
Case in point. During the “ice storm” we got help from the local Army guard unit to clear power lines. The got their Humvee (the real one) stuck, broke their winch and announced they would never return after spending their cutting time digging it out. This happened in the same area I “floated” through with my much lighter Toyota short bed with mud tires giving them hot coffee while the worked. It was all about the tires they had and weight because the snow/ice pellets cover was so deep. Then it was like in real estate… flotation, flotation, flotation