I tow a 5th wheel trailer with my 2005 2WD QC Hemi w/3.73 gears. I bought a new trailer that is about 10K lbs (old one was 8K lbs.) and am thinking of going to 4.10 or 4.56 gears. Was wondering if anyone has any experience towing this amount of weight using 4.10s or 4.56s, how much towing improvement there was and what the effect on MPG was? TIA for any info that can be provided.

 

4.10s won't be much of a change. The 4.56s will help the towing, but will hurt your highway mileage. The trade-off may be worth it if you really tow a lot.