No top end decrease?

WHy is it that I did 115 with stock gears and now top out at about 95-100? CAnt budge past it at all. Cant imageine with taller gears. I lost 15mph. It probably is not the same "gap" when you go to 4:88 from 4:56, but lets just take another 15 off, that puts you at around 80-85. Im not going by what I have read, "theoretical 210mph speeds", or even a math book. Im just going by what I have experienced with my truck and the gear/tire sizes.

All im saying is, in my opinion, it is too tall. I was just doing a guestimate, so what if i was a whole 473 RPM off. I saod "LIKE 3000". Dont be so literal.

2500rpm compared to 2300rpm @ 75mph

Lets say you go on a 2 hour long highway roadtrip...
Thats 2400 extra rotations of the engine to go the same distance at the same speed. To me, that sounds like alot of gas.

I live 2-1/2 hours away from home. I went from using 1/4 tank of gas, to almost half. Gears help low-end gas milliage, higher gear ratios kill your highway milliage.

"Learn how to do math"
Smart *** remarks arent appreciated. Go elsewhere.

I already know how to "do" math. Im an economics major. Lots o' math

 

 

Yes, no top end decrease. Are you talking about on tires? What size? Are you tuned? If not, than you never did 115 mph. The factory governor will prohibit you from doing more than ~99 mph with factory tuning. While being tuned, even running large tires and tall gears, you should be able to see 120+ mph. Not to mention that if you're talking about with the larger tires than you should be actually able to go faster than stock tires and stock gears without considering aerodynamics. Sorry but you're debating something that you're going to lose. I've had two 2004+ F150s, both were lifted, I know what I'm talking about here. If you had a 2004+ F150 on 35s and couldn't go past 115 mph with tuning than there is something wrong with your truck. Besides don't you know that these driveshafts and tires aren't speed rated for that. I don't think you realize how small of a difference there really is between 4.56s vs 4.88s. Typical person who is naive to the subject at hand and "fears the gear".

I just think you're making stuff up now. Unless you were driving way over the speed limit there should be no reason why you used double the gas. Consider this ... 4.88s and 37s are the same thing as 4.56s and 35s, correct? I never lost any mileage on the highway, only gained 1-2 mpg driving 70-75 mph while running 4.88s and 37s.

PS: Making stuff up isn't appreciated.

 

i cant believe you guys are seriously arguing over that. There really isnt much of a difference.

You want my opinion: go with 4.88s. Better power, and frankly you really shouldn't be driving a lifted truck faster than 70 or 75 max. 1) for fuel prices and 2) safety. Most mud tires arent rated to go too much faster than that anyways.

Fordboy, the difference between 4.88 and 4.56 isnt going to "kill" your mileage, the mileage is bad enough with 35" + tires anyways.

 

Let's try to stay on topic, okay?

 

 

I can do it too!!!

 

 

I like this one better ...

 

I see your Mexican and I raise you a Mexican

 

Shotgun.

 

1) yes, I have a programmer
2)governor is 105mph Unless my speedo is off, maybe that could cause the confusion.
3) No, I was going 60mph the whole way. I still lost an extra 1/8 of a tank.
4) before the new gears I didnt "top out" at 115, but it was a slowwww climb. With the gears, I DID top out at 85-90. Maybe there IS something wrong with my truck, I dont know. Just telling you based on what MY truck has done. ****, maybe your 2 trucks are one of a kind ford "super trucks". haha

YOur assuming i am making stuff up simply for Arguements sake. Im not, thats what happened, maybe there is something wrong with my truck? I dont know... The thing is, I was just giving my opinion, and you snapped back with a "your wrong, im right, your stupid" kind of attitude.

Maybe it is because with 4:56 gears the engine just cant produce enough power to go above 90mph. Im stuck at about 3000rpm. Did you take that into consideration? The gear ratio and math might add up to do 200mph, but if you dont have something to power it up to that speed and live in a world with limits such as our own, it aint guna' happen.


Everyone's opinion or knowledge is their own. Not everything someone reads in a forum is true, you have to think for yourself. I was just stating what I thought.

I am no Gear-expert and Nither are you. Sorry to all who were Interested in the ACTUALL topic, Im sure it will get back on track now. For the others, im sure it was entertaining! haha

Your right, Im wrong... Im sure your satisfied now, end of story, back on topic.

 

I agree with the safety thing. I did that back when I was in Highschool. Kids will be kids. Ive matured a bit since then and havent been over 80 in about 1 year....

I liked to go fast....

haha

 

1. What kind of programmer?
2. The factory governor is at ~99 mph. The factories are allowed a little bit of wiggle room though. So it's possible that the speedometer said 105 mph, but you were really doing about 99 mph. Are you talking about with your programmer?
3. It sounds like something is wrong with your truck, you should of gained mileage at that speed.
4. It sounds like something is really wrong with your truck or you've got the speed limiter just bumped up to 115 mph. I know I didn't have any type of super truck, that doesn't happen with tolerances now a days.

I'm not telling you that you're stupid. I'm just telling you that the advice is bad and people who do not know any better will just take it and not think twice. Trust me, I've seen it happen numerous times. I'm just trying to clarify something. If it came off that I was saying you were stupid, I apologize for that. Knowledge is power.

4.56s do not change any power that your vehicle has, just changes acceleration patterns. The power isn't what limits the vehicles top speed, it's the poor aerodynamics of the F150 or any type of large vehicle for that matter. If you are sitting at 3,000 RPMs and not gaining any speed or climbing in RPMs than you've got a tuning issue. It sounds like the speed limiter was just bumped up to 115 mph like I said earlier in this post.

 

Cool, the arguement tone of this thread is gone...


haha

I have a Diablosport Tuner. I have a slightly modified tune (for intake and such), but it is basically canned.

I get 10mpg, is this normal for a supercab with a lift, 4:56 gears, and 35" tires? I do a lot of city driving, stop and go. Seems a little bit low to me.

The truck runs fine and is actually very fast for what it is. I beat my friend's 5.3 lowered 2wd chevy with intake(Again, in highschool). It just becomes a dog when I hit that last gear for some reason.

I never corrected my speedo with the tuner. SO, the truck is doing about an extra 5 mph over what the speedo says, and it said 105 when I didnt have the tuner and hit that limiter. Maybe I got a rare fluke in the programming of my truck that allowed me to go a little faster...

Anyways, My truck runs good, no error codes or anything of that nature. It just must be my truck. Every truck is different in some way shape or form...

Now that I think about it, when you have an uncorrected speedo, the higher of a speed you go, the more it is off. So maybe im off by 10-15 mph by the time I hit those high speeds? Im off by about 6 mph at 70 actuall mph. So maybe I am toping out more at like, 100-105? Still doesnt ecplain the 3000rpm thing though.