There's no single "perfect" answer, as the ideal gear ratio depends on your driving style and typical terrain. However, a good starting point for a 2001 Ram 1500 5.2L with 35" tires is in the 4.56 to 4.88 range.
Here's why and some considerations:
* 4.56: This is a popular choice and offers a good balance between highway fuel economy and low-end power. It's likely to provide decent performance in most situations.
* 4.88: This ratio will provide more aggressive acceleration and better towing capability, especially off-road, but will slightly reduce highway fuel economy.
Factors to Consider:
* Your typical driving: Mostly highway? Lean towards the lower end (4.56). Mostly off-road or towing heavy loads? Lean towards the higher end (4.88).
* Transmission: The automatic transmission in your Ram will also influence the optimal gear ratio.
* Current Rear Axle Ratio: Knowing your *original* rear axle ratio will help determine the necessary change. Look for a sticker on the driver's side doorjamb, or check your owner's manual. This allows for more precise calculation of the needed gear ratio change.
* Tire Size Variation: Even 35" tires have slight variations in actual diameter between brands and models. Precise measurement of your tires’ true rolling diameter is best to ensure the accurate ratio calculation.
Recommendation:
Before making a decision, I highly recommend using a gear ratio calculator. Many online calculators are available; just search for "gear ratio calculator for trucks." Input your original gear ratio (if known), your engine RPM at a given speed (e.g., 60 mph), and your new tire size (35"). The calculator will help you determine the ideal gear ratio to maintain similar RPMs at highway speeds after the tire change.
Ultimately, choosing between 4.56 and 4.88 often comes down to personal preference and driving habits. Consulting with a professional gear installer or a knowledgeable off-roading enthusiast can provide valuable input tailored to your specific needs. They can also help determine if other drivetrain components might require upgrades to handle the increased stress from the larger tires and higher gear ratio.
