DURANGO CONVERSION
I own an older Dodge Durango that is currently equipped with the 360ci gasoline engine. My family bought this vehicle new and it’s been kept in excellent condition. I’m looking for a diesel drivetrain that could fit reasonably well and is affordable, and I'd like to keep my automatic transmission and AWD. Has anyone considered using a GM 6.2L or 6.5L for these sorts of conversions? Benjamin Gorst Via Email
The engine compartment in a full-size Chevy pickup truck is nearly 36 inches long from the firewall pocket to the rear of the radiator. This normally provides for 3-4 inches of clearance between the cylinder heads and the firewall and 3 inches clearance between the fan-clutch and the rear surface of the radiator. In general, the 6.2/6.5 requires nearly the same footprint as a GM big-block gas engine. So if the engine compartment in your Durango is close to these dimensions, then a 6.2/6.5 would fit, and it would provide good power for your truck. A non-turbo 6.5 with non-turbo cylinder heads would likely provide fuel economy in the mid to upper 20s when the vehicle is geared to produce about 1,800-2,000 rpm at your chosen cruising speed (in the 60-70 mph range). A turbocharged 6.5 with turbo heads will produce a little lower fuel economy, but still easily within the 20s as far as mpg.
A good automatic transmission choice for a non-turbo 6.5 would be GM’S 4-speed with overdrive TH700R4 (or later 4L60-E). The more expensive computer-controlled 4L80-E would be a better fit for a more potent 6.5TD that might see towing duty. In any case, the 1993 and earlier mechanical fuel injection system would greatly simplify the conversion. Mechanical fuel injection systems are more reliable, less expensive, simpler to get running and easier to dial in.
The 6.2/6.5 utilize the same motor mounts as previous Chevy/gmc V8 gas engines, which make it easier to adapt a GM diesel engine to a wide range of non-gm vehicles. We’d try to acquire an engine that includes a full set of accessory drive brackets, pulleys and even the accessories like the power steering pump, alternator and A/C compressor. A custom set of A/C hoses can be created to adapt the new compressor to your existing A/C system.