In this video, we take an in depth look at upgrading the camshaft and performing an MDS (Multi-Displacement System) delete on the Jeep Grand Cherokee WK2 SRT with the 6.4L Hemi V8. We compare a Series 1 and Series 2 Grand Cherokee SRT, both running a Stage One cam upgrade including custom dyno tuning
We break down why the MDS delete is critical for long term engine health, how much it costs, and what’s involved in the process. You’ll learn the risks of leaving the MDS system in place, the benefits of a Stage One cam upgrade, and why a Stage Two cam is a bad idea unless you’ve invested in a forged bottom end.
If you own a Jeep Grand Cherokee SRT, Ram, or Chrysler 300C with a Hemi V8, this is essential info. We also cover solutions for owners who’ve already suffered camshaft damage, including crate motor options, and clarify why the 6.2L Supercharged Trackhawk is exempt from these issues.
The MDS system was designed to improve fuel economy by shutting off cylinders at cruise, but it also creates uneven lifter action that wears down camshaft lobes. This wear sends metal debris through the engine and can lead to major failures. Removing the MDS system is the best way to protect your Hemi long term.
When carrying out an MDS delete it makes sense to install a Stage One cam at the same time. It provides more torque, more horsepower, and a tougher idle while keeping the stock look under the bonnet. It is the most cost effective way to add performance without reducing reliability.
Stage Two cams sound appealing but stock pistons and rods in the Jeep SRT are not designed to handle the extra load. Without a forged bottom end Stage Two cams can lead to piston damage and total engine failure.
An MDS delete alone usually costs between 10,000 and 12,000 AUD. Adding a Stage One cam brings the cost to around 12,000 to 14,000 AUD. While expensive, this work prevents even costlier repairs in the future.
An MDS delete is not just a software change. It requires the cylinder heads, lifters and camshaft to be removed as well as ECU reprogramming. This is why the job is complex, time consuming and best handled by a specialist.
For engines already damaged by worn cams and metal contamination, crate motors with Stage One cams are available. This offers a faster and more reliable solution compared to rebuilding a heavily damaged motor.
The 6.2L Supercharged Trackhawk is not fitted with MDS. These engines are free from cam wear caused by cylinder deactivation.
These recommendations are not limited to the Grand Cherokee SRT. Ram trucks and Chrysler 300C models with Hemi V8s face the same issues and can benefit from the same upgrades.
