Currently, anyone looking to get into a gas-powered Chevrolet Low Cab Forward 3500 or 4500 is limited to GM’s 6.0L L96 V8 engine. Although also offered in the LC8 compressed natural gas (CNG) configuration, the L96 is the only option with regard to gasoline power. Now, it’s looking like the medium truck line is poised to receive a new gas engine option in the form of GM’s 6.6L L8T V8.
For the time being, the Chevrolet Low Cab Forward line’s L96 V8 produces 297 horsepower and 372 pound-feet of torque. It’s an old workhorse of an engine, but it’s not the most power-dense, nor is it the most efficient. By contrast, the 6.6L L8T V8 is an all-new, modern truck engine. The L8T is not offered in a CNG configuration.
Indication that the Chevrolet Low Cab Forward truck was due to receive the new 6.6L L8T V8 can be found in new service manuals for the 2020 model year, which show the 6.6L L8T mated to the 6L90 transmission for the Chevrolet 3500/4500 (Isuzu NPR) series vehicles. Critically, this is the same powertrain combo offered in the 2020 Chevrolet Silverado HD and 2020 GMC Sierra HD pickup trucks.
So far, Chevy has yet to make an official announcement with regard to the inclusion of the L8T engine in the Chevrolet Low Cab Forward truck line. Interestingly, the 6.0L L96 V8 engine is still included in the service guides for the 2020 model year trucks, which would suggest that both engines will be offered in parallel.
The Chevrolet Low Cab Forward truck line is a series of medium duty trucks offered through a partnership between General Motors and Isuzu Motors. The line currently spans two generations, with 3500/4500 models slotting in as base model offerings. In addition to gas engines and CNG engines, the line is also available with Isuzu diesel engines.
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Comments
Since the compression ratio is much higher ( at 10.8 to one ) on the 6.6 liter than the old 6.0 liter engine ( at 9.6 to one ) the LPG propane and CNG fueled 6.6 engines will run fantastic. Propane is 104 octane and CNG is 120 octane, so they will produce at least another 11 percent more torque with the higher compression ratio plus another 10 percent because of the larger engine volume. With about 80 pounds feet more torque ( 464 ) in the 6.6 compared to the 6.0, they can use a lower rear gear ratio, which will save on fuel in urban or highway driving. Since the 6.6 engines are more efficient, they will also accelerate better too. Here in Canada the pump price of propane is about half the price of 87 octane unleaded gasoline. We always leave the gasoline systems in place when converting a car of truck, so it starts on gasoline, then automatically switches over to propane after running for 2 to 3 minutes. This dual fuel system, allows unlimited driving distance, in case there are no propane stations on your route. Propane has 37 percent hydrogen content so it burns very, very hot, but leaves no carbon in the combustion chambers or around the rings even after putting 1/2 million miles on the engines. The engine wear when running on propane is equal or better than a diesel engine. Gasoline engines can be serviced by more mechanics as well, allowing for faster service if any work must be done on the engine.
It will probably be the fastest medium duty truck you can buy! Have not heard anything about CNG/LNG conversions for the L8T yet, but it has been done to direct injection engines before.
That motor in the Chevy LCF is going to be a beast. Those trucks see steady sales. This will only help make them more attractive.
Perhaps more importantly – they need to add this new 6.6L V8 gasser to the Silverado 4500 HD, 5500 HD, and 6500 HD (conventional cabs).
Those conventional cab Silverado medium duty trucks are selling extraordinarily well considering they only come with a diesel and there hasn’t been much advertising. A gas model can push it to the top of the class.
The Silverado medium got off to a slow start but they are proving popular. I think a gas engine is on the way, my guess is it will be the 6.6L with a 6 speed Allison 2000 series transmission.
Such a joke they still use that garbage 6 speed.
Meanwhile they have two transmissions, the 8 speed and 10 speed 90 series that would be a massive upgrade.