I have a few questions...

Has anyone redlined their GX470?

We're still at 500 miles.... not sure if it's time to redline or not....

Just wanted to ask a question... when you're stopped and floor it, the automatic transmission does shift at redline in each gear, right? Don't want to expect it to and then not

How rev-happy is the 4.7l? I noticed it has a rather low redline as the tach shows.

 

With the 1st 1000 miles you should try and stay around 3-4rpm, I have never exceeded 3rpm for the 1st 700-800 miles after that I hit 3.5 and 4 a little, all the cars I even had got excellent gas mileage, talkin abnormally high compared to their identical makes

I would not suggest redlining it until you hit a grand but if you your gonna redline it like I do wait till you hit 5000miles so the engine is worn in more and then just manually shift it into 1st, put the pedal to the floor and run it up to redline then shift into 2nd, 3rd, you get the idea, don't worry you can't mess up anything the truck has rev limiters so you can't even get the needle in the red

Is this your 1st car cause no car shifts at redline from a stop with the pedal down, the trucks whole purpose is to get good fuel economy, shifting at redline is not fuel efficient.

4.7 likes the lower range on the tach, where all the power is

 

No it's not my first car... the lexus is my mom's. When I floor my car from a stop, it redlines every gear (6500 RPM). It only redlines if your pedal is all the way at the floor. I don't have to put it in tiptronic mode to do that.

 

These trucks don't have tiptronic mode

 

I know, but you implied using the shifter to dictate when the tranny shifts.

 

what I meant was you can actually manually shift it, it has 1st to D which is overdrive 5th

 

What are you talking about? What kind of car wouldn't go to redline if you floor it??? I can't think of a car I've driven that does that.

 

Wants the point to "redline" the vehicle?

The power or torque is at it's most beneficial at LOW revs. Look at the engine specs and especially the POUND FEET OF TORQUE (LB/FT)

Thats what the engine is well noted for!

More revs dont mean more power!

Well, theres a data collector on the car anyway so if you screw the engine up by over revving it at least they can tell you why it blew up!

 

Well, actually, you're wrong.

Power = torque x RPM / 5252. If you're trying to attain maximum acceleration, you redline in every gear, especially since the GX's horsepower peak is at 4800rpm (redline being right around 5000rpm). Sure, the GX produces most of its torque low in the rev range, but every car does. Torque plateaus and falls as horsepower rises.

Many people say that when you approach redline, your power falls. That's exactly right. They say that you shouldn't even go to redline, because you're just wasting time since you're not making much power past the power peak. This is a common misconception, however, because you have to account for gearing. Sure your power drops a bit, but when the transmission shifts, it will fall right into the power peak in the next gear - perfect for maximum acceleration. No wonder every car tester I've ever seen when doing acceleration tests redlines every gear.

So to sum it up, generally, more revs do mean more power.

 

Dont know which engineering college you attended but try this out!
I guess you are destined to race around at high revs!

Torque versus Power

In the simplest terms, torque is the twisting force the engine applies to the crankshaft and then on to the transmission.

Power, by contrast, is measured as the torque times the rotational speed. In imperial measures, one horsepower is equal to 550 foot-pounds (of torque) per second. Two engines can produce the same power but have very different torque ratings for the following simple reason:

One horsepower can be produced by moving one pound 550 feet OR by moving 550 pounds one foot, provided that either function is achieved in one second.

The difference comes in the fact that the high-torque engine will be rotating slower than the low-torque engine at the same power output but it will be twisting the crankshaft a lot more vigorously.

In theory, different gear ratios - most commonly four or five in cars' gearboxes - should mask different torque characteristics by altering engine speed to suit but the reality is that engines which produce high torque figures at low revolutions respond much more readily in give and take driving.

The practical advantages come in the form of reduced gear changing, lower engine revs and wear and, invariably, lower fuel consumption in all conditions other than constant speed driving.

For Mr Average, torque is therefore more important than horsepower, unless you spend your life racing around at high revs.

 

I do not need a lesson on torque vs. power. I have a very solid understanding of the concept, especially after reading much techical literature over the past few years. And actually, I didn't attend an Engineering school. I'm 17.

For maximum acceleration, you redline the car. Period. Sure, cars are much more responsive from a stop if they have high low end torque. But an all around fast car needs horsepower too, and horsepower is attained by revving the engine.

These topics have been thoroughly discussed in the Car Lounge over at VWVortex. It's nothing new.

And I'm not "Mr. Average," as you say. I am a person who asked if the engine is able to be redlined safely, since some of our past cars did not want to. Now that we have over 1500 miles on the GX, we have redlined it several times and have achieved maximum acceleration. Thank you.

 

Well keep reading the technical material.

Red lining an engine at anothers expense is a very hard way to learn the lessons!

Hopefully you won't have to foot the resulting bills for damage caused.

It's sometime hard to explain to youth that reading a few articles does not make you an expert!

The GX is not a racer!

 

brent0226
what do you mean by achieved maximum acceleration

 

You guys crack me up. What do you mean "at another's expense?"

It is perfectly fine to "redline" an engine, as long as you don't do it every 5 minutes. That's why the factory put that redline there. It is to warn that past this point, you could cause damage. And it's funny that you derogatorily say "youth" as if we were an inferior species. I am an extremely learned person. I spend an extreme amount of time researching cars. Who are you to judge me?

Of course the GX is not a racer. We would have gotten a sports car if we had wanted that. We do, however, expect a luxury vehicle to have some guts, which the GX has. When we need to merge onto a busy freeway, we will redline the engine if we need to merge. That, EDGE2, is what I meant by "maximum acceleration."

 

Guys....

Do you really think Lexus would let you destroy one of their engines for being an idiot? These engines have rev limiters built into them to prevent the unintentional redline (i.e. gear shifting into neutral under hard acceleration). However, that does not prevent anyone from being a moron such as driving on the highway in 1st gear. It is your call if you want to destroy a 40+ thousand dollar car.

Btw, one last comment..I've learned that NOT everything on the internet is TRUE