Jump to content

BFGoodrich All-Terrain T/A KO2 increased weight


AhuraPro

Recommended Posts

Posted

I noticed immediately that the KO2's drove differently and had a much different turn-in. Discovered today the SR-As weigh 39.8 lbs and the KO2's weight 55 lbs!

 

That's 61 lbs difference!!

 

Not that it matters too much but DAMN!

 

 

  • Replies 32
  • Created
  • Last Reply
Posted

I felt it big time when I put on 285's in place of the stock 245's.....oh my. Took a while to get used to it, but now I have compromised with 265's.

Posted

Switching sizes is never a fair comparison. My ATPs weigh quite a bit more (I think 13 lbs ea) than the SRAs and I haven't found my mileage to be lower. Tracked 18,000 miles on Fuelly. Also, I spent almost $200 patching the 4 ply tires, 0 patches in the 10 ply so far (knock on wood).

 

The main difference is the SRAs don't grip AT ALL lol.

Posted

Then you are lucky, every work truck and personal truck I have ever had loses 1 to 3 mpg going to a larger, heavier, more aggressive LT tire. My 2012 F150 work truck went from 19mpg to 17.5 mpg going from the stock hancooks to wrangler AT Kevlar LT.

Posted

Switching sizes is never a fair comparison.

Just going to a heavier tire isn't going to change much. Tread compound and tread will affect mileage, but nothing will affect it as much as going to a bigger tire.

Posted

I went from stock SR-A's to Toyo MT's at 71 lbs each. Stop and go traffic takes a mpg loss, but I can still get 21 mpg on the highway.

Posted

Just going to a heavier tire isn't going to change much. Tread compound and tread will affect mileage, but nothing will affect it as much as going to a bigger tire.

Actually it does, been well documented...

 

It is a combination of them all but weight does play a large roll. It is called rotational mass and when increasing that by 15 lbs per wheel (seems to be close when going from a P to a E tire) that can increase weight by around 20% combined per tire assuming a 18 inch wheel weighs say 30 lbs and stock tire is 40.

 

Not to mention it slows acceleration, the midsize guys really feel the hit of a heavier tire.

 

Tyler

Posted

I counteracted the heavier tire weight by adding a Magnuson MP1900 TVS Supercharger and American Racing Headers.... take that you big ole heavy tires!!!!

Posted

Actually it does, been well documented...

 

It is a combination of them all but weight does play a large roll. It is called rotational mass and when increasing that by 15 lbs per wheel (seems to be close when going from a P to a E tire) that can increase weight by around 20% combined per tire assuming a 18 inch wheel weighs say 30 lbs and stock tire is 40.

 

Not to mention it slows acceleration, the midsize guys really feel the hit of a heavier tire.

 

Tyler

If you've taken a high school physics class you know that weight doesn't matter much once something is in motion. Once the vehicle is rolling and the tires are turning the effects of weight are negligible. But, the more aggressive tread, width, large diameter, compound all matter.

 

Yes, it'll make a small difference in acceleration but not much more than running big rims.

Posted

Right, weight is a big player in stop/go situations, not for highway cruising. But most people spend most of their time in stop/go situations, so it's a decent factor.

Posted

I could care less, I'm keeping my KO2's and buying them again when these wear out. If you are concerned about weight, keep the stock street tires.

Posted

If you've taken a high school physics class you know that weight doesn't matter much once something is in motion. Once the vehicle is rolling and the tires are turning the effects of weight are negligible. But, the more aggressive tread, width, large diameter, compound all matter.

 

Yes, it'll make a small difference in acceleration but not much more than running big rims.

 

Nope, never have taken that class :wtf:

 

Correct, at a static speed on level ground it isn't much but it still changes something. Any variation that causes a need for more power to offset (say a hill or needing to speed up some after slowing down some) it will decrease.

 

Now originally you said it isn't going to change much. Well if your city mpg drops by say 10% and you drive 50% of the city, that will lower your overall average no? Unless you are able to get a push start to highway speed and only drive that, you are going to lose mpg and have to account for that.

 

How much one considers "much" is up to each discretion, but 2 mpg average on a vehicle averaging 19mpg to most isn't minimal, that is over 10%...

 

Tyler

Posted

I noticed immediately that the KO2's drove differently and had a much different turn-in. Discovered today the SR-As weigh 39.8 lbs and the KO2's weight 55 lbs!

 

That's 61 lbs difference!!

 

Not that it matters too much but DAMN!

 

 

Lol you didn't do any research before you spent money on a new tires?

I counteracted the heavier tire weight by adding a Magnuson MP1900 TVS Supercharger and American Racing Headers.... take that you big ole heavy tires!!!!

I like your style!

 

Sent from my SM-G900P using Tapatalk

Archived

This topic is now archived and is closed to further replies.

  • Latest Articles

  • Posts

    • Yes. You need to check out that thing, and the hub further.
    • Would this be normal or a worn CV Shaft? 51K miles 3.5" lift? Boots are intact and no visible leaks showing. Attached is a the video I took. Thanks     https://youtu.be/ZnW7PPRmjJY?feature=shared    
    • If everything checks out at the MAF, then the MAF is BAD, new or not.   You don't need a signal generator to troubleshoot this. PCM needs ALL powers and ALL grounds able to light a halogen headlight bulb - if it can light the bulb bright, then the wiring is good enough to run the PCM.   Best thing you can do for yourself is spend some time here: scannerdanner.com - Check out all his YouTube videos on similar issues. If you decide to subscribe it's the best bang-for-buck ratio in the automotive world, hands-down. He's got TONS of free vids on YouTube, too.
    • Yes, I used my multimeter to probe all of the wires at the MAF, both with the sensor connected, sensor disconnected, key on engine off, key on engine running, etc etc etc. I probed all of the wires again at the PCM, at the connectors, etc. All voltages are what they should be according to the service manual/wiring diagrams. All grounds are good, less than 20 millivolts from the battery negative under load. Both at the connector of the MAF, at the PCM connector etc.      I know this throws a pretty big wrench into things, but this truck was acting up before the swap. I don't have very much information, if any on what was causing it, but if you cleared all of the dtcs it would do the same thing where it would crank, fire, then die. And it would do the same thing a dozen or so times, and eventually it would start and run, but the difference is that it would run and actually be drivable. Whereas now if you can drive it at all, it goes into reduced power mode almost immediately, and even then it's not running correctly. When you come to a stop at a light it stumbles down to for 500 RPM before catching itself and returning to the smooth idle. And if you go more than about 50% throttle then it immediately goes back to doing the misfire thing.    Like I said, I know that throws a wrench into things, and unfortunately I was not able to pull any data or anything like that before I did this work, so I don't have much to go on.    I'm trying to not fixate on one particular thing as the cause of the problem, but it seems like all avenues are pointing me towards the PCM. Like I said I have tested the wiring extensively (see above), and during cranking the sensor does produce seemingly legitimate values at least according to my multimeter, but as soon as the engine fires those values quickly descend into gibberish. I've tried it with multiple different known working sensors, I have done literally every test I can think of multiple times on the wiring (probing the signals, probing the pins with the sensors unplugged, probing the pins at the PCM, voltage drop, voltage drop under load, continuity, ohms, and double-checking everything against the wiring diagrams/ proper values in the service data.)    Another thing that pushes me towards a possible PCM failure is, I have noticed in troubleshooting a little bit taking a break and coming back, that when I leave the truck to sit for a while and cool off, it starts and runs smoothly when I first start it up. However once it warms up. It starts having problems. For example, when I went out to the truck this morning after it had been sitting overnight, I was actually able to drive it down the block. And then once I got on the throttle a Little bit after going about a thousand ft, it started misfiring again. I pulled it back into the driveway, shut it down, and started it back up. It idled smoothly. As soon as I touched the throttle it did the misfire thing again. From then on as soon as I started it it would misfire. I shut the truck off and went to go get a coffee and do a bit more research. When I came back out I started the truck up and it immediately went into the smooth idle. After a couple of minutes of playing around with it, it would not idle smoothly anymore. Let it sit a couple of hours, rinse and repeat. This makes me think with temperature change something is going wrong inside the PCM. I have the PCM out of the 2007 donor vehicle and I'm thinking of getting a one-day subscription to the ACDelco programming service to try and program that and see if it helps.   Like I said, I'm really trying to not fixate myself on one potential cause, but it seems everything is pointing me towards PCM failure. I would really like to try to confirm that, but unfortunately I don't have an oscilloscope or a signal generator to do the GM service procedure where you feed 5 khz into the signal pin. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...