Engine/Transmission (1998.5 - 2002) Thoughts on tire size choice?

[sgoeing]

I've got a 99 quad cab 4x4 automatic with 3. 55 gears. It currently has 285/75R16. I leave my edge Juice on level 1, but I'd really like a little more go around town (75% of my driving) and I need new tires.



So, I'm thinking about taking the tire size back down to 265 or even 245 to get better gearing around town. Either of these solutions should up my RPM's at 75mph to no more than about 2050 instead of the crazy low 1900rpm I'm running at now.



I'm really leaning toward going all the way down to 245's, but I can't make up my mind. Does anyone have any thoughts on this?

 

[sgoeing]

has no one else thought/done this?

 

[AMikesell]

I am in the same boat as you are on tire size. I am running 285/75R16 and like the look but dont like having my speedo off and the overhead computer giving false info even just a little after I have run them. If I was to buy new tires I would go with the stock 265 size to have everything back to normal unless you have a programmer that can adjust for the tire size than go for the 245 and enjoy better fuel economy either way. Just my 2 cents. Andrew

 

[GCULP]

DITTO, I have 285's and have not been happy with either the around town acceleration or the freeway speed towing, both seem to make it work just a little more than it feels like it wants to. I'll be going back to at least 265's

 

[Ted Constantine]

not a tire comment but this your around town/stop and go driving i would move the juice setting up to 2 or 3. I might be wrong but I am under the impression that the juice on level one you are actually at less than stock fueling off the line.

With 4. 10 and a 6 speed the smallest I can go and still drive on the highway is 295. I dont see a performance issue until 35"

Just choose a tire size that will bring you to 2000rpm at your desired cruizing speed.

 

[sgoeing]

75mph @ 2k rpm is 30. 9" tire diameter on my truck.

265's are 31. 6" so the RPM will be a little under that.
245's are 30. 5" so the RPM will be a little over that.


I can adjust speedo so that's not a consideration.


I have the Juice for monitoring and mileage; that's why it's on 1. I drive my engine fairly cold quite a bit and just take it easy, so turning up the Juice really doesn't mean anything (I have the cold engine protection on).

 

[cArNiVaLwOrKeR]

Im running 285's now and will go to 245's, wondering if anyone has yet done that?

 

[jeepit]

I thought a long, long time about this subject and ended up changing my mind at tire dealer to saty with the 265's as opposed to going up to the 285's. The bigger tire looks nice I agree. .

 

[CNeubauer]

My truck is close to the same setup as your's and it had 305/75-16s on it when I bought it and I went down to 265s when it needed new tires. The gearing on the 265s is nicer and I think it drives better with them too.

 

[VolsFan]

I run 285's on mine, I imagine I am taking a hit in fuel mileage, but they do look good. 245's would be more practical, however, will they work on a 16x8" rim? I know 245/75's came on the stock chrome plated steel rims, but they were 16x6 1/2"

 

[DCreed]

lets get back to basics here. 285/75/16 the first #285= tread width, the next #75= the cross section or essentially the height, then the last#16= the wheel dia. So if you want to keep traction and width then drop the 2nd # to 70 or even 65 and the total height will drop but the 285 width will remain.

 

[NoSeeUm]

Gear Ratio Calculator



My guess is about 150 rpm gain going from 285 to 265 and then about that for 265 to 245.



Jim

 

[DPrew]

I've run 245, 265, and 275 with 3. 54 gears and a 6-speed. The 275 BFG AT's would not balance well at all and required ceramic balancing beads to calm them down at speed. The 275 RPM's were a little low.

265 AT's were good but the D rating was just OK. 265 Bridgestone Duelers with E rating are my choice. These tires are bigger than my stock 245's but still tow 17-18K loads up extreme grades with no problem. The 265's look decent on the truck but the 245's would look pretty skimpy especially if you have offset wheels and fender flares.

 

[terrywerm]

I used to have 285's and loved the way they looked. They were also great for off-road especially in soft ground, as the floatation was better than the narrower tires. Since I pull trailers quite a bit, I replaced them with 265's and I like them better for that. It's also nice having the speedometer read correctly. Fuel mileage is quite a bit better with the 265's as well.