Tip Submitted by Doug Hildreth 8/2002 (email: firebird@mind.net)
My early training and my subsequent study of the Banks literature, along with the usual anecdotal reports talking to fellow RVers, convinced me that I needed a Banks system. The Banks literature claims that the improved airflow through the engine results in an increase of 80 horsepower and 140 foot pounds of torque.
We picked up our Aerbus in Lancaster and a commercial Driver took us and our rig to Las Vagas, delivering it to us out of state. He was very impressed with the power and performance of our Ford V-10 with the Banks as compared to the many similar vehicles he had driven over the same route. Pulling the hills we were 10 mph better than he was used to. From that point on I was very pleased I had ordered the Banks. The rest of the trip home impressed me directly as the driver with the power and the honest 9mpg gas mileage. Subsequently I have remained very pleased with the Banks.
Although I have been overjoyed and very impressed with the Banks, the Ford V 10 transmission has a “gap” between second and third gear. This means that when towing, on some hills, third gear is too high and second gear is too low. Since top speed in second gear is just over 40 mph, this means that you must down shift to second, since third gear is not low enough to hold the speed, and since second gear provides enough power but is a little too low, you must hold at 40 all the way up the hill to prevent excessive rpms. Not terrible, but there must be a way to make things better for those few times- I would estimate 20-30 % of mountain driving- when the gear gap causes a problem (severe pilot impatience).
Enter the Gear Splitter. I have a US Gear model (cost installed approx. $3,000). This is a small gearbox that bolts to the back of the transmission and it has two “speeds” in the gearbox. One is “normal”, and the other is “low”. This effectively gives you 8 forward gears instead of 4.
When in normal, everything is exactly the way it was before you added the unit. But when you shift into “low” range, you get four gears, each of which is half way between your “normal” gears. Effectively this means that when you are pulling that hill you have to drop from fourth to third. As the hill steepens, you know that third is not going to hold your speed and that second will be too low a gear, so you engage the gear splitter (shift it to “low”) and you are in third gear of the low range, or in two and a half (half way between second and third), which is just right. The other choice is to shift the gear splitter to the low range as you reach the bottom of the hill. This effectively puts you in three and a half, half way between fourth and third. Now as the hill steepens, you push in the button on the end of the gearshift lever (i.e. shift into “third”), and you shift from three and a half down to two and one half (half way between second and third).
The US Gear unit is a direct gear-to-gear unit (no internal clutch), so it can be used as a downhill engine brake. Again, going down that hill, we drop from fourth to third, but still are gaining speed. We know that we could slow to 35 mph and shift to second, but with the gear splitter we have a gear which is between second and third (two and a half) and just like going up the hill, this ends up being the perfect gear for coming down the hill. On steep hills you may need to brake occasionally, but nothing like when in normal third gear. When I first purchased the gear splitter, I assumed I would use it mostly for climbing and maybe a little for downhill engine braking. Now I feel that the downhill braking is more important and more used than going up hill. Consider this when choosing brands.
The gear splitter control button is mounted on the gearshift lever. It is activated by pushing the “high-low” button while the engine is under a slight load (gentle pressure on the accelerator). Then let up on accelerator pressure. A heavy “clunk” will be heard and felt as the lower gear set is engaged. Then resume the accelerator pressure. The same procedure is used for shifting back from “low” range to “high” (normal) range. Technically the splitters come in over and under drives, but on a practical basis in a motorhome, underdrive is the only reasonable choice.
It is my strong opinion that the Banks air intake and exhaust system is an excellent addition to any motorhome. It has demonstrated dramatic improvement in my V 10. It is my opinion that the older Ford 450 and Chevy 454 will improve even more noticeably than the newer engines. There is an improvement in gas mileage but that is not the reason to get one: It is the additional power. And again you will probably notice more improvement when towing. Flatland folks who seldom visit the mountains may not feel it necessary. The cost is in the range of $2500.
I would definitely recommend doing the Banks first. There is no doubt you will be impressed. Then see whether you think you need more rpm between your stock gears. Consider how much you drive in the mountains. Consider how much you tow. How much do you need that lower gear for braking downhill in addition to hill climbing?
