TheHEMI.com

If the legacy 383-horsepower, 5.7-liter Hemi V-8 won't cut it for your hauling needs in the next-generation Dodge Ram heavy-duty pickups, hang on just a bit longer. An all-new 6.4-liter Hemi V-8 is on its way by 2011 with power ratings of between 450-hp to 500-hp, according to our sources.

The 6.4-liter V-8 is said to be based on Chrysler's current SRT8 high-performance 6.1-liter Hemi V-8, but with a larger bore and longer stroke optimized for use in three-quarter-ton and one-ton truck applications instead of street racing. The engine is already being tested on the road in HD Ram engineering mules. There's no word on what transmission it will use, but ZF's new six-speed gearbox designed for gas or diesel engines might work.

An SRT-tweaked version of the 6.4-liter is also expected to debut in the 2012 Jeep Grand Cherokee SRT8.

Reliable source oh2o has confirmed that the 6.4 liter V8 engine for Ram trucks is slated for the 2014 model year. He believes that the company is targeting over 20,000 6.4-equipped Rams per year, which would mean that the company is building more 6.4 Rams than 6.4 SRT cars.

The 6.4 will be sold in both Ram Heavy Duty pickups (2500 and 3500) and the Ram medium duty chassis-cabs (3500, 4500, and possibly 5500), which are heavier-duty than the Ram pickups. Adding a gasoline engine would enable Ram to substantially drop the entry level cost of these trucks, providing better “first glance” comparisons to Ford. While most buyers will still opt for the diesels, having a similar base price may prevent some fleet managers or individual buyers from ruling Ram out at the start.

Allpar reader “AutoTechnician” discovered the 2014 owner’s manual for the 2014 Ram 2500/3500 on the Chrysler web site. He wrote that it mentions:

* A 6.4 liter V8 engine
* A rear air suspension
* Factory bed-liners

The 6.4 liter engine has, until now, been the exclusive domain of SRT cars, but Allpar sources have predicted its use in trucks for over a year. The engine will not be a 470-horsepower powerhouse like the one used by SRT, but will be tuned for truck use.

We believe that the big gasoline engine will be used as an entry level option on Ram 4500, which currently comes with a standard Cummins diesel, adding to its baseline cost. With the 6.4 Hemi in the mix, the base price can be dropped for better comparisons against Ford; but most buyers will still probably opt for the durable diesel.

The rear air suspension has also been rumored for two years. Allpar source “Dom” predicted both 6.4 Hemi and rear air suspension, along with a new automatic transmission (this may have been the Aisin AS69RC released with the 2013 Ram 3500), last June.