At first glance Santanimal looks like just about every other exhibition monster truck on the circuit. It's big, it's loud, and it's brightly painted. But the 4WD 1985 Ford F-250, owned by Bob Thompson of Bellevue, WA is really quite different from other monster trucks.
It doesn't crush cars. In fact, it can't crush cars. However, it can do something no other monster truck can do. It is capable of making 360 -degree turns within its own wheelbase and doing 360-degree turns while doing wheelstands. Furthermore, this truck can stand in place on its hind wheels all day long -- even when the engine isn't running!
Before you say, "that's impossible," keep in mind that this truck was actually designed with a purpose in mind that would take it away from the adoring crowds. Bob wanted to build a vehicle that could be used up in the oil fields of Northern Alaska. Vehicles up there have to be able to operate under all kinds of conditions and they have to be capable of driving across the delicate tundra without harming it. What's this got to do with a wheel standing monster truck? Well it turns out that the hydraulic drive system that makes day long wheelstands possible is also perfect for use in the Arctic. This 8 1/2-foot tall monster depends upon hydraulic pumps and lines to do its tricks.
There is no transmission, driveshaft, U-joint, differential, suspension system, or rear axle behind the 460 Ford engine (bored out to 495 CID). There is also no front axle, driveshaft, transfer case, steering linkage, shocks, or springs. The "axles" you see in the pictures are actually aluminum tubes that house the hydraulic servos, pumps, and lines. The 500 hp Ford 460 engine is hooked directly to the main hydraulic pump. This pump has the same function as the transmission in a conventional truck -- it transfers power to the driven wheels.
Each wheel has its own hydraulic motor. Fluid in the main pump is distributed to the drive motors at each wheel. The truck moves forward or backwards by the driver increasing the pressure in the lines and controlling the direction in which the hydraulic fluid flows. To get the truck to turn in a circle, the driver simply stops one or more wheels from turning. A right turn, for example, requires that the right rear wheel stop and the right front wheel turns slowly while the two left turn at normal speed. Wheelies are a bit more complicated. As the truck moves forward, the main hydraulic pump moves a series of weights in the cargo box from behind the cab to over the rear wheels and 360-wheelstands require a combination of operations.
Like most monster trucks, Santanimal is big. It is 10 1/2 feet wide, 20 feet long, and a towering 15 feet tall when in the wheelstand position. Overall weight is about 12,000 lbs. and there is over 360 feet of hydraulic hose. Bob runs Goodyear 44x41x20 Super Terra tires with under 5 lobs of air pressure in them to carry all this weight. The result is a tire print that is gentler on the tundra than a human foot as the truck fairly floats over the surface.
So next time your out in the Artic and you hear a big-block roar, it may just be Santanimal making all the noise.... or maybe one of those "Big Footed" creatures!
Last update: March 21, 1998
IT IS ILLEGAL
TO REPRODUCE ANY PORTION OF TRUCKWORLD.COM® PLEASE POST ALL TECHNICAL QUESTIONS TO
OUR READER FORUM Click here to send us your comments or questions. SEND NON-RETURNABLE
PHOTOS/ SLIDES/ SCANS TO: © COPYRIGHT 1996-2003 TRUCKWORLD
ONLINE! ® PRIVACY STATEMENT ALL RIGHTS
to the TRUCKWORLD ONLINE! ® Home Page
WITHOUT WRITTEN PERMISSION
WE CANNOT ANSWER ALL E-MAIL -- BUT DO READ EVERYTHING!
See how your company can profit with a web page or advertise on TRUCKWORLD ONLINE! ®
TRUCKWORLD ONLINE! ®
Cottage Grove, Oregon 97424
IT IS ILLEGAL
TO REPRODUCE ANY PORTION OF TRUCKWORLD.COM®
PLEASE POST ALL TECHNICAL QUESTIONS TO OUR READER FORUM
Click here to send us your comments or questions.
PHOTOS/ SLIDES/ SCANS TO:
© COPYRIGHT 1996-2003 TRUCKWORLD
ALL RIGHTS RESERVED
Back to the TRUCKWORLD ONLINE! ® Home Page