I will be going from the stock 245's to a 315/70/R17 tire on 17x9 rims with an RCD 6" lift soon. I tow a 26' Gearbox toyhauler which is probably around 9500 lbs loaded.

I will not be regearing and, from what I've seen from my searches, I probably don't have to. What revs do you think I would be turning at highway speeds and what might I lose in power?

Originally I was planning on doing a 4.5" RCD lift with 295's on 16x8 rims but I really like the look of the 315's. I went to a 70 tire and a 17" rim to try to lessen some of the squirm. How much do you think this would lessen the squirm and how bad would it be?

Thanks, Mark

i had green keys and 3" lift blocks and 315/70/17 for about 4 months and towed a couple times. it deff luggs the engine towing 7k but it isnt to to bad! i had it on setting 40 when i towed the trailors. i think 65 would of been better but i wasnt expecting to do a tranny up grade! the tires hold up just fine just make sure the air preasure is correct on them! it shouldnt be a problem!

I don't have an edge or predator...yet...so I'm at stock power levels.

When you are not towing, about what RPM are you turning when doing 65?

Do you feel any noticeable squirm?

I pull a 33' 5er that weighs in around 10.5k pounds...the truck is stock except for what is listed in my signature. Yes, you will loose power...given. I have the 6 speed and if I manage the hills manually instead of cruise control, I have not encountered too many issues. At 65 MPH, the engine is turning approximately 1500-1600 RPMs...a little outside of the torque curve.

I are all 4 tires to 50 PSI and let her rip...no handling issues.

Good luck and happy camping.

MaxRock

I tow about 8,000pd and the rpm at 60-65 is around 1650-1750.

I tow with the hypertech on level 3 and I have no issues with power. I have not towed stock with the 315's so I can't compare but I would imagine you will be out of overdrive or using the t/h all the time. Currently I rarely have to take it out of overdrive, whether because of temps or power. I wouldn't want to tow without the hypertech and 315's, I think I would feel like I was back with a gasser.

I am going to purchase a 5er that is 14,000pd loaded. I will regear for that, but only for preference of wanting to stay in od.