Engine revving high at speed

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Engine revving high at speed

Postby Mikelux76 on Thu, 11 Oct 2018 6:11 +0000

Have a 2012 hilux dual cab, 4 speed automatic. Have just recently purchased the car and have just done some long distance driving. About 20 mins into the trip was sitting on 130km( speed limit in the nt) and about 2500rpms travelling nicely along a flat bit of highway when the rpms went up to 3500rpms and if I went faster the rpms would continue to rise until almost redlining. If I slowed down it would go back a gear and rpms would come down but as soon as a I sped up the rpms would shoot up to 3500rpms or high. This problem would only stop if i came to stop turned the car off and and then started ag ain but after about 20mins it would start again.

Anyone have any suggestions on what the problem would be or where to start looking.

Cheers micheal
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Re: Engine revving high at speed

Postby Myralga on Thu, 11 Oct 2018 6:39 +0000

Might simply be you are right on the edge of the gear shift, engine load sense etc. something as simple as the a/c and then the viscous fan hub both being engaged plus the 130kmh bring enough load on the system that it drops a gear. And revs up.

I have recently spent a couple weeks driving a 2.8l Prado where my daily is a 2.8 Hilux.
The auto Prado always wanted to kick back a gear at funny times. Drove me nuts where in the manual lux I know the torque will get me trough the same spots.
Toyota’s auto trans are not the most refined products out there I must admit. And part of the reason I still have a manual.
Also the autos certainly seem to be a lot thirstier for similar set ups in my opinion.


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Re: Engine revving high at speed

Postby Mikelux76 on Thu, 11 Oct 2018 7:19 +0000

I'm pretty sure it is not a gear change, as I said have gone through all the gears and am driving on flat/straight road. At 130km should be thru all the gears in a 4 speed auto. Just seems like it is not normal, I will be driving along not changing speed and it just revs high and won't stop.
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Re: Engine revving high at speed

Postby Mikelux76 on Thu, 11 Oct 2018 7:22 +0000

The engine would still rev high at 100km as well after about 20mins of driving, I wasn't towing anything and all that was in the tray was two engels and three suitcases.
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Re: Engine revving high at speed

Postby DeadlyBeast on Thu, 11 Oct 2018 8:58 +0000

How many km on the odo?
Been fairly hot up there... no trans temp warning light on the dash?
Checked trans fluid level?
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Re: Engine revving high at speed

Postby aandy on Fri, 12 Oct 2018 4:09 +0000

My 2012 use to do that, before I fitted a trans cooler.
It would do it on the beach and also in the 130 zones. (130 isn’t a practical speed for a Hilux anyway)
I’ve never had a trans temp warning light but when it got really hot it would no longer stay in 4th, I’d say it’s programmed like that.
Larger diameter tyres probably don’t help either.

I’m not guessing here, it did it for 80k kms without cooler, hasn’t done it in last 100k kms with cooler

Fit a really big trans cooler and I’d bet your problems will go away.
Also, change/flush the oil in your auto. Buy a 20l drum of Penrite and search on here for procedure.
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Re: Engine revving high at speed

Postby grunf on Fri, 12 Oct 2018 7:00 +0000

is this in the right section?

:D :shock:
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Re: Engine revving high at speed

Postby Mikelux76 on Fri, 12 Oct 2018 7:08 +0000

98000km on clock, no warning light on dash and just checked fluid level last night, only took it for a 10min drive but level was just below low notch on hot notches, so will drain fluid and fill again. What section should it be in grunf?
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Re: Engine revving high at speed

Postby DeadlyBeast on Fri, 12 Oct 2018 10:09 +0000

Good spotting Grunf
Moved from Gen 8 engines to Gen 7 drive train components

Yep - good idea to drop the fluid after 98K - especially if hasnt been done before.
Let us know what the fluid looks like - better still post a pic if you can

All things trans cooler related here: Trans-cooler stuff

How to flush your 4 speed - link and location on last post. Details for correct fluid in the Auto Trans Service thread
4 speed auto


Get your self a cooler before the flush if time is on your side - will just save some dicking around, spilling fluid and topping back up to correct level at a later date

Davies Craig 678 coolers are a good common option.
A good thread below:
Auto trans cooler - does size matter?
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