Low RPM Growling Sound

[basicxj]

Please correct me if i'm wrong in my understanding.
This growling sound is happening because of lugging i.e we are at lower rpms but the system is asking for an upshift in gears as apparently that's how Toyota got the fuel efficiency with this v4 'hybrid' motor. Assuming that previous point is correct, I would think driving in ECO Mode the whole time should be better right since in ECO mode, it stays in the current gear longer therefore the system isn't looking to upshift

ECO mode will most likely see the engine "lugging" more than it would in Normal or Sport mode. The TRD exhaust will have some drone at certain RPMs and load conditions. Try the other modes to see if that impacts anything, and if you can pin the offending noise you speak of down to the exhaust, consider swapping to the OEM non-TRD version. There may be a take-off factory exhaust available if you have someone nearby who has upgraded theirs to TRD or aftermarket.

It could also be that the Land Cruiser's quirks are not going to be what you are after in the big picture, and if that is the case trade-in value should be decent if you really need to be driving something else.

V4 engine - Wikipedia

en.wikipedia.org

^^ just so you don't become laughed at, your Land Cruiser's engine (as mentioned) is an inline 4

 

[wpage]

OK so you have a custom exhaust with matched with a improved air intake will give you some performance advantage. However, for you and possibly your neighbors some noise. You will need to decided what is more important and in line with your family needs.
Evidently someone befor you wanted some extra boost...

 

[D-mac]

This growling sound is happening because of lugging i.e we are at lower rpms but the system is asking for an upshift in gears as apparently that's how Toyota got the fuel efficiency with this v4 'hybrid' motor.

The TRD Performance exhaust you have has been tuned to make a certain sound. If you go on YouTube, you can check out comparisons of your TRD exhaust's sound vs. OEM Toyota, or other aftermarket LC250 exhausts like Borla, NYTOP, Magnaflow, Revel, aFE, AWE, Remark, etc.

 

[unkn0wns0ldier]

yes inline 4 lol my bad ... i was parallel processing with work stocks and this.

 

[GR8Santini]

Soldier - You have like around a $1100 TRD exhaust package, that sounds like you may not have actually wanted.
Starting point is to ask your dealer to help, & see if they’ll straight swap the system onto a in-stock unit.

 

[LC250MD]

yes my LC has the cat black exhaust

There’s your answer. I specifically shopped for a non cat back model though I recognize others like it

 

[unkn0wns0ldier]

Thanks guys! I went to the dealership today and asked for a ride along and the foreman was nice enough to spend close to 30m 45m and explained a lot about the engine and the exhaust especially the fact that this has a low freq noise by design which is why you hear it more in the cabin rather than the stock. Thanks everyone for all your inputs! loving this forum

 

[basicxj]

So it was the exhaust?

I contemplated upgrading, but in reality I have been fine with stock. It wasn’t a port or dealer installed option last year when we were Land Cruiser shopping. Maybe one day.

I don’t know how many miles yours has on it, but many aftermarket exhausts settle down/mellow after racking some miles on them.

 

[unkn0wns0ldier]

So it was the exhaust?

I contemplated upgrading, but in reality I have been fine with stock. It wasn’t a port or dealer installed option last year when we were Land Cruiser shopping. Maybe one day.

I don’t know how many miles yours has on it, but many aftermarket exhausts settle down/mellow after racking some miles on them.

That's what the foreman said but fundamentally it has to be more than that since it doesn't happen at all RPMs. What is so special about the low RPMs that would cause this? As far as mileage go, I have 600 miles on it so hopefully this exhaust does settle down. In case anyone is wondering why buy it then if I knew it had the cat back exhaust? Well, during the test drive this growling wasn't noticed since I mostly drove around locally so constant RPM raise and braking. Other time was spent looking at the features and the family's comfort. This was only noticed on the highway cruising for a 3 hour road trip so you can imagine my shock when this was discovered after hitting the highway. As people have said, I'm hoping to find a happy medium between our ears getting acclimatized, exhaust settling in, and playing with the different modes like ECO locally and sport on the highway.

 

[ultane]

yes inline 4 lol my bad ... i was parallel processing with work stocks and this.

Next time you perceive the beast growling at you, put your hand on the gear shift knob thingy, and gently move it one click to the left, and get back with us… pretty please.

 

[basicxj]

That's what the foreman said but fundamentally it has to be more than that since it doesn't happen at all RPMs. What is so special about the low RPMs that would cause this? As far as mileage go, I have 600 miles on it so hopefully this exhaust does settle down. In case anyone is wondering why buy it then if I knew it had the cat back exhaust? Well, during the test drive this growling wasn't noticed since I mostly drove around locally so constant RPM raise and braking. Other time was spent looking at the features and the family's comfort. This was only noticed on the highway cruising for a 3 hour road trip so you can imagine my shock when this was discovered after hitting the highway. As people have said, I'm hoping to find a happy medium between our ears getting acclimatized, exhaust settling in, and playing with the different modes like ECO locally and sport on the highway.

You’ll experience more lugging in Eco mode where the transmission tries to keep revs down through selecting a higher gear, and that will bump the exhaust drone quotient up.

For break-in I’d keep it in normal mode rather than eco. Less lugging, less time spent at a certain RPM. You want to keep RPM varied.

 

[GR8Santini]

That's what the foreman said but fundamentally it has to be more than that since it doesn't happen at all RPMs. What is so special about the low RPMs that would cause this? As far as mileage go, I have 600 miles on it so hopefully this exhaust does settle down. In case anyone is wondering why buy it then if I knew it had the cat back exhaust? Well, during the test drive this growling wasn't noticed since I mostly drove around locally so constant RPM raise and braking. Other time was spent looking at the features and the family's comfort. This was only noticed on the highway cruising for a 3 hour road trip so you can imagine my shock when this was discovered after hitting the highway. As people have said, I'm hoping to find a happy medium between our ears getting acclimatized, exhaust settling in, and playing with the different modes like ECO locally and sport on the highway.

I actually like the lower tone exhaust, & removed the rear resonator. No drone at all on the highway. I think your main center muffler should have a small dead end pipe coming out of it - 1/4 wave or Helmholtz pipe to reduce exhaust drone. Those mufflers can take a few 1000 miles to break in.

Try Sport mode for a few days. I think whether stock exhaust or modified, the LC performs & sounds better in Sport mode - especially around town. Usually this keeps the tranny a gear or two up from in Norn or Eco, & we seem to get better mileage as the vehicle isn’t bogged down in a higher gear. Also it will start in 1st or 2nd, so doesn’t bog leaving a stop.

You can have my resonator if you’d like, just pay to ship from TX.

K