There are a few engineering wonders during my career that have been something to talk about beyond electronic engine controls and ABS. I was an early believer and purchaser of automated manual transmissions (AMTs) and automatics because of their ability to widen the range of available drivers that no longer could shift a single stick or two stick quad box, to give us some additional fuel economy and to reduce shock loads on the drive trains.
We got all of that. And now with the transmission talking to the engine and both agreeing when to shift to keep the RPM's low, they have opened other options beyond automated shifting.
I believe many fleets would have purchased automatic transmissions for regional Class 8 tractors, but the up front cost (huge), the fear of repair costs and driver negativity ganged up on a great option, so they never took off.
Today the small tuck market is dominated by automatic transmissions and no one should even consider anything else. I also believe that AMT’s or automatics should be the choice for all vehicle purchases.
Although there still is some cost difference, there is something to consider in AMT’s replacing the manual transmission. That is the CLUTCH.
Clutch life under normal conditions use to exceed 600,000 miles and replacement time was about 5 hours including resurfacing the flywheel ($50) and the truck was back in service in one shift. The clutch itself was about $300, and the labor rounded out at 8 hours time added about $600. Easy math, $1000 or $.0017 CPM, about 2 tenths of a mile cost.
Now with the new technology and limited driver shifting skill sets, you must prepare and budget for higher maintenance costs. Today the dealer repair time is about 16 hours of labor exceeding $110 per hour, plus triage charges, ($2,000 ish). The clutch cost is in the range of $3500 for a captive part in some cases and a flywheel in most cases is beyond turning, so a clutch replacement has become a $6,500 repair. And if the iron gods are in your favor you may gotten to 500,000 miles.
See how that affects the weekly budget when you pay that invoice. The math now becomes a penny 3, $.013 CPM, almost eight times the cost of the old days.
Because there is limited experience with automatics in Class 8 non-vocational high mileage vehicles, the experience in failure rates or repair costs are someone limited. But what we all should think about is that the used truck market will catch-up with the knowledge, and trade or sale prices will reflect a reduction in trade value to compensate for clutches not replaced..
I still believe either AMTs or automatic transmissions are the only options to consider. Planning and budgeting for clutch costs are real and will in some cases reduce the residual value in the end. Considering thaat,automatic or automated transmissions’ up front option cost may not be as salty as one would think. To me, one or the other is the only way fly.
Simplicity, a cheap clutch and the five-speed transmission are gone. Budgeting and planning is in, or should be.
