I just got a pair of used 245/75 R16 tires from a friend. So I mounted them up on my old aluminum mags and mount the 245's on rear axle of the truck. 

 

 

They are a bit shorter in height. The gains are great!

 

Engine load is reduced by 5% to 10% roughly. 

EGT's are about 50*F lower.

Acceleration is way better and faster. 

Cruising RPM's are right about 1,960 RPM at 65 MPH.

 

I've got to reset my cruise timing limit on the Quadzilla I need to drop from my current 25% to 20% it was holding cruise timing climbing about 2-3% grade. 

 

I'm going to document MPG usage as well in the coming days. 

Edited July 2, 20186 yr by Mopar1973Man

Towed 800 miles this wkend with a 28' enclosed trailer around 6000lbs thru Virginia and West Virginia mountains using 245/75/16 tires. Towed very well, around 2300-2400rpm at 58-62mph locked in third (OD off) on my 47re. Great power, great engine braking with a 12cm/.70ar exhuast housing on my 62/68 Borg sxe s300. Better towing characteristics than my 265/70/17 set. Got 10.5mpg on the way there with timing set to bottom of the green range on the quadzilla, and 12.13mpg on the way back on the exact same stretch of road returning with timing set to medium of the green range on the timing sliders on the quadzilla. Also drove 60mph on the way back and 50-55mph on the way there because it was dark and raining.

In 2016 I was sled pulling for the points championship in my class, so I hit all the pulls for United Truck and Tractor Pullers of Utah. 13,500 miles in 6 Rocky Mountain states and averaged 11.78 mpg. This is with my Edge Juice (to the nay sayers), 3.55 gears and 285/75x16 tires. The combination weighs 19k.

 

I am thinking real serious about going back to 265's soon. For lower final drive ratio, my truck is a little too high for my trailer to sit level and my tire chains don't fit the 285's. They are also a little cheaper which is a good thing. Oh yeah, I did win, lol

 

 

I've been enjoying the 245's. way more power on the highway I can accelerate much faster now. Still the MPG is not changed much. Still drifting around the 19 MPG with winter fuel now in full swing. The higher final ratio really does make a huge difference in acceleration. I like the fact I can remain in 5th much longer now. I'm in my top gear sooner. 

Edited November 15, 20186 yr by Mopar1973Man

On ‎11‎/‎15‎/‎2018 at 5:08 AM, Mopar1973Man said:

I've been enjoying the 245's. way more power on the highway I can accelerate much faster now. Still the MPG is not changed much. Still drifting around the 19 MPG with winter fuel now in full swing. The higher final ratio really does make a huge difference in acceleration. I like the fact I can remain in 5th much longer now. I'm in my top gear sooner. 

 

I just did a  round trip from Salem, OR to Medford, OR and back (500 miles) with the 245's to pick up an excavator bucket.  No mpg reduction - 20.2 mpg at 65 - 73 mph.  Got slowed to 45 mph up steep grades a couple of times in southern Oregon - stayed in 6th gear and accelerated  quickly back up to 65 mph.  I'll never go back to the 265's.

 

- John

7 hours ago, Tractorman said:

I'll never go back to the 265's.

I'll never go back to the 285. 

This pizza cutter disease is spreading, thanks a lot Mike....

27 minutes ago, Dieselfuture said:

This pizza cutter disease is spreading, thanks a lot Mike....

 

 

45 minutes ago, Mopar1973Man said:

 

 

It's not funny 

I want my truck to look mean so people yield at 4way stop signs, I swear they did more often with bigger tires 

Now my truck is only cool then I first Fire it up in the parking lot, everyone has to turn around and see if a semi is coming. 

4 minutes ago, Dieselfuture said:

It's not funny 

I want my truck to look mean so people yield at 4way stop signs, I swear they did more often with bigger tires 

Now my truck is only cool then I first Fire it up in the parking lot, everyone has to turn around and see if a semi is coming. 

 

I love the sleeper mode. "Ah, just a stock truck I can whip it." Yeah right. I actually hunt for 4th Gens with lift kits and minimum of 35" inch tires. Those jacked up 3rd and 4th gen I kill for fun. No problem. Surprises everyone when the tires let go and the truck is gone. Where did it go?!?! 

 

My design is all about shedding all the excessive drag and maximize my torque value. Which I've done. 

Edited November 20, 20186 yr by Mopar1973Man

19 minutes ago, Mopar1973Man said:

 

I love the sleeper mode. "Ah, just a stock truck I can whip it." Yeah right. I actually hunt for 4th Gens with lift kits and minimum of 35" inch tires. Those jacked up 3rd and 4th gen I kill for fun. No problem. Surprises everyone when the tires let go and the truck is gone. Where did it go?!?! 

 

My design is all about shedding all the excessive drag and maximize my torque value. Which I've done. 

 

This is what happens to the NV4500, 3rd gear boosted launch with 600 hp, not mine

 

 

Umm... this is what I did back on the Edge Comp and +50 HP injectors. Before even the Quadzilla or the +75HP injectors. The 245's let out more torque than the 235's did. This is nice because of fewer chances of breaking stuff again. 

 

 

Edited November 20, 20186 yr by Mopar1973Man

I can't even spin my tires unless it's slick or wet out, must be good tire or my tune. Just got rid of some tires and rims I bought to temporary use and was going to do a burn out, after few attempts feeling like I'm going to brake something I gave up. But on few occasions I spun tires going up a wet hill

1 hour ago, Dieselfuture said:

... and was going to do a burn out, after few attempts feeling like I'm going to brake something I gave up.

 

I wait until it snows to do my burnouts.  That way I can make my truck last longer.

 

- John

17 minutes ago, Tractorman said:

 

I wait until it snows to do my burnouts.  That way I can make my truck last longer.

 

- John

Yeah I really don't like doing it, but on an old set of tires I thought why not, just once, just for fun, and then I remembered all the hard work I did to this pile of bolts and decided not to lol. 

6 hours ago, Dieselfuture said:

I can't even spin my tires unless it's slick or wet out, must be good tire or my tune. Just got rid of some tires and rims I bought to temporary use and was going to do a burn out, after few attempts feeling like I'm going to brake something I gave up. But on few occasions I spun tires going up a wet hill

I am a bit leary of of doing it myself on dry pavement with all the drive shaft joints wth 450k on them but let the roads get damp and mine will break loose when the turbo lights in most gears. 

14 hours ago, dripley said:

but let the roads get damp and mine will break loose when the turbo lights in most gears.

 

Cheater... 

When i had the edge juice i did a burnout in front of an idiot in town that was acting rude towards me. My truck very nearly got out from under me it had so much power. Even this morning the roads had a very light thin frost and i easily can spin my tiures with my current mods.

4 minutes ago, Marcus2000monster said:

When i had the edge juice i did a burnout in front of an idiot in town that was acting rude towards me. My truck very nearly got out from under me it had so much power. Even this morning the roads had a very light thin frost and i easily can spin my tiures with my current mods.

5

 

Quote

3rd gen 17s with 285/70/17 Goodyear’s,

 

Ummm... that easy to explain. Wider tires spread the weight out more so traction is reduced on slick surfaces. Axle weight typically in the rear axle of a 2500 series is about 2,860 pounds so about 1,430 pounds per tire. Then figure out the catch patch in square inches and then divide up the weight to amount of square inches. Wider tires tend to float more on top, great for offroad usage.

 

This is another reason I've gone down in tire size this, in turn, makes a smaller contact patch and pushes more rubber into the road on slick days. Yeah, you have to manage the power vs. your road condition. Typically when the frost is visible I typically drop to level 3 (no wiretap) I tend to get a torque shock as the wiretap hits. 

39 minutes ago, Mopar1973Man said:

 

 

Ummm... that easy to explain. Wider tires spread the weight out more so traction is reduced on slick surfaces. Axle weight typically in the rear axle of a 2500 series is about 2,860 pounds so about 1,430 pounds per tire. Then figure out the catch patch in square inches and then divide up the weight to amount of square inches. Wider tires tend to float more on top, great for offroad usage.

 

This is another reason I've gone down in tire size this, in turn, makes a smaller contact patch and pushes more rubber into the road on slick days. Yeah, you have to manage the power vs. your road condition. Typically when the frost is visible I typically drop to level 3 (no wiretap) I tend to get a torque shock as the wiretap hits. 

IM buying a parts truck with 3;54s this weekend. theyre going into my truck and then im downsizing my tires

20 minutes ago, Marcus2000monster said:

IM buying a parts truck with 3;54s this weekend. theyre going into my truck and then im downsizing my tires

 

I'm interested in how that goes... Keep us posted on that!

O.K.  So I found some LT265 75 R 16 Take offs from someone that went Big.  So those are going on to start with.  I did notice that now I have to drive the truck up on wood otherwise my chest hits, when I try to crawl underneath, where as I used to have clearance.  Just got the IQuad installed after a months delay.  Had the Truck in the body shop getting the skin cancer cured and some wrinkles removed.  Installed the IQuad to it throwing codes that the MAP sensor voltage is low.  So I'm sure the IQuad won't function correctly.  Now to see why that and the oil pressure sensor that share the 5v source don't work.

 

Michael

Edited November 21, 20186 yr by int3man