Are they just for loading? hills? spare tires?
2006-06-12 06:46:44 · 10 answers · asked by missy 4 in Cars & Transportation ➔ Other - Cars & Transportation
well roads have a wieght restriction per axle. and if the truck has more wieght on the truck then the axles allow he can drop an axle to shift wieght and reduce the wieght per axle making him legal.
2006-06-12 06:50:52 · answer #1 · answered by mournyngwolf 3 · 3⤊ 0⤋
For load distribution.......to distribute the weight of the truck evenly to all the axles. With 18 wheelers they are allowed 12000 lbs. on the steer axles (the ones in the front) 34000 lbs on the drives ( the ones that are actully pulling the unit) and 34000 on the trailer( what is being pulled) Hope this information will help you. If you want anymore info feel free to IM me...will help if I can.
2006-06-12 06:55:00 · answer #2 · answered by Meaty 2 · 0⤊ 0⤋
You often see this on dump truck,too. They are used when the truck is loaded so they can haul more weight. They are raised when empty or lightly loaded so it reduces wear on the tires. Normally a air operated system.
2006-06-12 16:52:19 · answer #3 · answered by Beavis Christ AM 6 · 0⤊ 0⤋
most are spares but some are used for very heavy loads
2006-06-12 07:20:43 · answer #4 · answered by laura468 5 · 0⤊ 0⤋
THEY ARE NOT SPARES the extra wheels are for weight distribution to keep the per axle/per wheel weights legal
2006-06-12 07:32:34 · answer #5 · answered by ErasmusBDragen 4 · 0⤊ 0⤋
for the same reason regular cars do..its a spare in case of emergency
2006-06-12 06:50:11 · answer #6 · answered by sir COPE 2 · 0⤊ 0⤋
They're spares.
2006-06-12 06:49:34 · answer #7 · answered by CarlaCCC 5 · 0⤊ 0⤋
spares
2006-06-12 06:49:23 · answer #8 · answered by dwh12345 5 · 0⤊ 0⤋
for really heavy loads and when dumping
2006-06-12 06:49:24 · answer #9 · answered by mi_gl_an 4 · 0⤊ 0⤋
When they are carrying heavier weights they lower them,
.
2006-06-12 06:49:57 · answer #10 · answered by Joe 6 · 0⤊ 0⤋