I feel like I need to correct a few statements that were made. Going with 20's instead of 17's is going to reduce your ability to tow by about 1,000 lbs.

This is all from memory, so bear with me if my numbers are a little off:

First, the max tow rating for the Dodge Ram is about 9,100 lbs when properly equipped (RCLB 17s & 3.92). You should not tow over 9,100 lbs according to Dodge with any setup (10k is not something it's rated for).

Secondly, stepping down to 3.55 gears loses 1,000 lbs. b/c of gearing. Stepping up to a crew cab loses 1,000 lbs b/c of weight. And stepping up to 20s over 17s loses another 800 - 1,000 lbs (can't recall the exact number) due to the added unsprung weight. (It's not a gearing thing b/c the diameter of the 17's with tires is about the same as the 20's b/c the 17's simply have a taller sidewall). If you get 4x4, then you lose another 500 - 700 lbs b/c of the weight of the extra equipment.

The trucks main limitation is not power but the suspension setup. A F150 can tow a lot more with that crappy 5.4 b/c of the chassis and suspension setup. It will struggle more at 6,000 lbs than a Ram, but ultimately it can tow more. With the suspension being the limiting factor, any additional weight decreases ability.

I did a lot of research on this before buying to make sure a 2wd Crew Cab with 3.55 gears and 20's could tow my boat and trailer. My truck has about 6,500 lbs towing capacity. The same truck with 3.92 gears has about 900lbs more capacity. I had a hard time finding a laramie with the 3.92 in my area so i went with 3.55 b/c it was sufficient (and slightly cheaper and can potentially get better mpg). 17's weren't an option for me b/c i was getting a Laramie.

 

Btw, a 4x4 Crew Cab Ram 1500 w/ 20" wheels has about 5,500 lbs of towing capacity. That is plenty for your 4,500 lbs trailer. That capacity is limited by the suspension setup, as previously stated (and I'm sure Dodge is conservative on that anyways). The Hemi however should pull that trailer like it's not even there.

So, the decision should come down to the other factors: looks, price of tires, ride quality, etc.

I love 20's and wouldn't have it any other way. With my new 305/50/20 tires I will have better traction and more stability while towing (really helps with trailer sway, high winds, etc.) and therefore I prefer 20's when towing.

 

The 5500 lbs towing capacity you mentioned. Is that with the 3.55 or 3.92 rear end?
And thanks for all the great information. It's really helpful.

 

That was for the 3.55. 3.92 should gain you 750 - 1,000lbs.

 

Sold on the 20" wheels then. We go tomorrow to start dealing and looking for a new 1500. Thanks again.

 

go with 24s!!!




lol.. just kidding

 

You just get those put on Doc? Look good. But you're not doing any serious towing.

 

sobo im not towing anything.. i dont even have a hitch anymore lol

 

Sobo, all of your very useful information got me to look a little more into towing weights.
I found this info on the dodge.com website. For the following truck.

2009 Ram 1500
RAM 1500 LARAMIE CREW CAB SWB, 4x4, 5.7-Liter V8 HEMI MDS VCT Engine,
5-Speed Automatic 545RFE Transmission


Truck #1
With 3.92 Axle Ratio and null You Can Tow 8300 lbs
Gross Vehicle Weight Rating(GVWR)[i]=6800
Payload[i]=1258
Curb Weight[i]=5542
Curb WeightFront / Rear=3170/2372
GAWR[i]Front / Rear=3900/3900
Gross Combination Weight Rating(GCWR)[i]=14000

Truck #2
With 3.92 Axle Ratio and null You Can Tow 7300 lbs
Gross Vehicle Weight Rating(GVWR)[i]=6800
Payload[i]=1248
Curb Weight[i]=5552
Curb WeightFront / Rear=3183/2369
GAWR[i]Front / Rear=3900/3900
Gross Combination Weight Rating(GCWR)[i]=13000

I can't tell what the differences is that reduces towing capacity by 1000 lbs between truck #1 and #2??

Anyone have any thoughts?

Thanks.

 

From the info posted I can't see a difference between those two trucks. It could be wheel size?

So I did some searching around and I couldn't find the article with all of the detailed info on towing and various configurations, but I did come across this:

"Tire size and rear axle ratios make a big difference pulling a trailer. If you switch from 17-inch to 20-inch wheels, keeping the 3.92 final drive ratio, you’ll lose 1,100 pounds of towing capacity. If you keep the 20s but select a 3.55 rear axle instead of a 3.92, for better fuel economy, it drops another 1,000 pounds, for a max of only 7,000 pounds, in the regular cab.

Our Ram Laramie Crew used a 3.92 rear ring and pinion and blinged-out 20-inch wheels. Maximum towing was rated at 7,300-lbs. If the truck had been equipped with 17s and a 3.92 back axle, we’d have gained more than 1,000-lbs. of towing, to 8,400-lbs."

That's from a review in the Dallas News. It also states:

"Maximum towing for the new Ram is 9,100 pounds, in a HEMI-powered regular cab short-box 4x2 running on 17-inch wheels and a 3.92 rear axle, and outfitted with a class IV receiver and tow package. The small print in the Ram’s specs states maximum towing capacity assumes the truck has a gross combined weight rating of 14,000 pounds, with a 150-pound driver."

So, more or less what I stated previously was correct. From 17 - 20" wheels you lose 1,100, the 3.92 to 3.55 you lose 1,000lbs and I know the other article said you lose 1,000 for the crew cab and like 750 for 4x4 and that makes sense since it's based on weight or gearing.