Question about axle Ratios

Galena wrote:
Looking at two, 2017 RAM 1500 Laramie Trucks. One has a axle ratio of 3.21 and has a lot of options I like. The second one has a ratio of 3.92 but with less options, prices on both are very similar. Looking to purchase a TT with a gross weight of 7500 to 8000 pounds. Am I ok with the 3.21, assuming I will not be doing a lot of mountain driving?

Actually you'd do better with a Chevy (wink-wink). Seriously, I had a Chevy 1500 5.3 with a 3.2something rear and a smaller TT weighing in around 6500lbs. It struggled even on the gentle hills here in south Texas. My opinion is get the 3.92, think it will do a much better job towing.

Good Luck either way....

Check the available payload on the yellow sticker! Ram's generally have the lowest payload capacity of the half tons and 8000 lbs is really at the outside of what most folks would tow with any half ton. From a quick playing around with the RAM towing guide a 4x4, crew cab, 6' box Laramie with the hemi only has 1,300 lbs of payload capacity which means after even one passenger you're looking at a max trailer weight of ~6,500lbs. A quad cab 4x2 Laramie with the short box might work for the low end of your range. As far as the 3.2, forget it, even Dodge doesn't rate that at 8,000lb and they're assuming a much easier tow then the barn door that is a travel trailer.

The 3.21 is a great hiway gear but lousy for towing. Stick with the 3.92 and you will be very pleased with the towing performance.

afidel wrote:
Check the available payload on the yellow sticker! Ram's generally have the lowest payload capacity of the half tons and 8000 lbs is really at the outside of what most folks would tow with any half ton. From a quick playing around with the RAM towing guide a 4x4, crew cab, 6' box Laramie with the hemi only has 1,300 lbs of payload capacity which means after even one passenger you're looking at a max trailer weight of ~6,500lbs. A quad cab 4x2 Laramie with the short box might work for the low end of your range. As far as the 3.2, forget it, even Dodge doesn't rate that at 8,000lb and they're assuming a much easier tow then the barn door that is a travel trailer.

^This!

2017 Laramie? For the money I would get a used basic model 3500 srw.

ScottG wrote:
The 3.21 is a great hiway gear but lousy for towing. Stick with the 3.92 and you will be very pleased with the towing performance.

No, the OP won't be "pleased" as he'll never get as far as actually towing a trailer this heavy because he'd certainly exceed the truck's payload capacity, regardless of axle ratio. No question about it, 3.92 is far superior to 3.21 for towing but that won't in any way compensate for lack of sufficient payload capacity. :(

Galena wrote:
Looking at two, 2017 RAM 1500 Laramie Trucks. One has a axle ratio of 3.21 and has a lot of options I like. The second one has a ratio of 3.92 but with less options, prices on both are very similar. Looking to purchase a TT with a gross weight of 7500 to 8000 pounds. Am I ok with the 3.21, assuming I will not be doing a lot of mountain driving?

No! First things first that is way too heavy to pull with a 1/2 ton truck not to mention stopping it safely. As far as gear ratio goes I personally would never by a tow vehicle with a gear ratio less than 3.73. Any lower and you just bought you a slug.

Help me understand some of the comments like the one afidel posted. Looking at the RAM towing guide, http://www.ramtrucks.com/en/towing_guide/ it indicates 9600 for the model I am looking with Ram, just trying to understand all the comments. Thanks

ulvik wrote:

Galena wrote:
Looking at two, 2017 RAM 1500 Laramie Trucks. One has a axle ratio of 3.21 and has a lot of options I like. The second one has a ratio of 3.92 but with less options, prices on both are very similar. Looking to purchase a TT with a gross weight of 7500 to 8000 pounds. Am I ok with the 3.21, assuming I will not be doing a lot of mountain driving?

No! First things first that is way too heavy to pull with a 1/2 ton truck not to mention stopping it safely. As far as gear ratio goes I personally would never by a tow vehicle with a gear ratio less than 3.73. Any lower and you just bought you a slug.

Just so you will know. a 3.73 is a much lower gear than a 3.21, and a higher gear than a 3.92. It is backwards to many. The higher the number. The lower the gear, and of course, the lower the number the higher the gear.

As for the TT. We need real weights. Only the weighed GVR means anything


to the OP. You want the lower 3.92 gear. No matter what TT you buy. It will make life easier for you, and put less strain on the truck.

Galena wrote:
Help me understand some of the comments like the one afidel posted. Looking at the RAM towing guide, http://www.ramtrucks.com/en/towing_guide/ it indicates 9600 for the model I am looking with Ram, just trying to understand all the comments. Thanks

The tow rating is a useless gimmick number. You'll far exceed many other limits, specifically payload, axle, and tire ratings before coming anywhere near the tow rating.

For example, a crew cab Laramie only has about 1100lbs of payload available with a tow rating of around 10k. The payload needs to include the tongue weight of the trailer (figure 13 percent of loaded weight) driver and all passenger weights, any cargo, and the weight of the hitch. An 8k trailer would have a tongue weight of ~1040lbs. Add another 60lbs for the wd hitch and you've reached your payload before the driver alone got in the truck. If you had a family of 4 that weighed 600lbs, you would only have 500lbs left for the tongue weight. That would be a tt around 3500lbs loaded!

Most trucks in that situation pulling big trailers are over loaded. Not the end of the world to exceed payload ( within reason) but you definitely don't want to exceed your axle and tire ratings which you won't be far off of if payload is exceeded.

Welcome to the world of 1/2 ton trucks.