Originally Posted by Nematocys
OK, now I'm confused. I took a look at the article you linked to and did see the double asterisks, specifically the comment that you would have to deduct 1100-1150 lbs for 20" wheels, off of max towing.
What is confusing me, is that a while back I came across a post that had a link to a very handy pdf (rammlup1500.pdf) titled "2010 Ram Base Weights/GCW/Payload/Trailer Tow 1500" - sorry I didn't find / provide the link or original post as a reference.
But in that pdf, I looked for my truck specifics to see what my towing limitations are, and for a Crew Cab 1500 4x4 SLT (they didn't list Sport - just ST, SLT, and Laramie) they listed several different combinations (tires, engine, gears).
And what they had listed for mine, P275/60R20, Hemi, and 3.92 gears, was a max trailer of 9900 lbs, and payload of 1380 lbs (and a base weight of 5393).
By comparison, for the same vehicle, but with P265/70R17, there was only a 50 and 40 lb difference...9950 / 1420 (and a base weight of 5351).
They also had another tire option, LT275/70R17C - which had the same numbers as myine with 20's...
So I'm wondering what numbers I should be using when looking to stay under for towing safely? The 9900 - or 1100 off of that?
And if the wheel size effects your max towing, would it also lower the payload capacity?
I only ask because I'm looking to buy a new RV (possibly a short & lightweight 5th wheel), and I am using these numbers to narrow my search options...