4.0 automatic high RPM cruising

With the mechanical LSD and the truck (as its an 08 sport) in neutral, both tires will spin the same direction due to the clutch packs in the diff. It takes ~ 150 ftlbs of torque to overcome a fresh set of clutch packs in the mechanical clutchpack lsd diff.

 

When you started in L, and shifted up through. Did you stay in 4th for a bit (before shifting to 5th) and let it climb to 2800ish rpms while light on throttle?, Im betting you though the "shift to fifth" is actually the torque converter locking in 4th.

 

I'll give it another shot and make sure to stay in 4th until the rpms climb.

 

I would drive it in 5th at highway speed, then shift down into 4. If you're making 5th gear there should be a BIG jump in RPM as it unlocks and goes to 4, then a second or two later there will be a small 100-200 rpm drop as the torque converter locks. If you shift from 5-4 and there's no change or a small 100-200 rpm change that just means it's already in 4th and the the TC is unlocking.

 

Thats a good way to tell as well.

 

So I went out and shifted from L to D and then back down to 4. I filmed it, Check out how slow I'm going in each gear relative to the RPM.

 

I'd say everything is functioning properly. Must be re-geared.

 

Try recording this test again (3-4-5) at a constant 50MPH. From what you've shown it looks like there is no 5th gear TC lockup.

 

It sound like you have 4.88 gear... or 5.29 gear... Or could just be your ABS sensor that is no good/b broken/ damage dirt... either way you want to start there. Could, just could be your abs that is throwing signal to the ECM to turn on A Trac to get you the proper grip, ECM think you are loosing traction...

 

I guess it’s time to call on our buddy @gearcruncher
Since it seems you have stock gears, it looking more like a Trans issue.
The guy above may know more.

 

Going by the info given in post #15.
It looks like he has stock gears.

 

Whelp shit. 4th to 4th lock up occurs at 40-41 secs just before you shifted to 5th. and 5th lock up at 44-45 secs as the camera moved to the other side of the dash.

You are re-geared sir, trans is functioning properly.


OP is your truck 4x4? Im curious if so. Stopped. put it in 4hi, and roll forward slowly till everything clicks in. IN A STRAIGHT LINE, try to accelerate slowly, if it doesnt want to or feels like things are binding STOP and put back into 2hi.

If the above is the case (meaning front diff is stock ratio and rear diff is this 5.29+), Me thinks the rear axle of the truck might of been swapped with a full doner axle (after original shit the bed somehow) without ratio being checked. Makes no sense to run such a gear in a stock tire'd truck.

 

Yeah. 5.88 puts him at that rpm.
But he says the driveshaft didn’t even spin 4 full turns.

kind of confusing to me

 

@douglasfir I suspect you actually have an incorrect year instrument cluster installed. A potential odometer fraud case. Why I don't know. a clean carfax doesn't mean a whole lot when you do your own work on your truck and keep it out of reportable accidents. The "Atrac" light is in the exact spot for the "lights on" indicator. Toyota changed the gauge layout when it implemented the new changes in 2009.

The first assumption is you have a cluster out of a newer Tacoma and it might have been from a 4 banger. Potential different RPM calculations used.
The second assumption, you may have and incorrect gauge overlay whether it was from another stock cluster or custom from Black Cat Customs.

I don't think you have been regeared since the speedo is only off by a mile. that would be within the acceptable tolerance range - assuming you still have stock sized tires on it.

I would carefully find a spot where you can do this next part. Stick the truck in first gear, drive and briefly find out where the rev limiter starts at on the gauge. i have a manual but I believe it should be around 5500. if it's way higher than that, then I would say the cluster is out of a 4 cylinder.

edited for correct year*

 

from the videos.... it doesn't sound like you are really pushing the engine in relation to the RPMs (sound-wise). I don't have a stock exhaust but even my engine is more audible at those same RPMs versus the video.

 

what's your idle speed when sitting in park with the truck warmed up? This will take the regearing out of the equation.

 

Was there a 5 speed auto 4 cyl Tacoma? His gauge cluster shows for a 5 speed auto.
Perhaps he does have an incorrect cluster, but out of a later year Tacoma since I don't think the 2008's have A-TRAC. But I could be all wrong.

 

I believe all the 4 cyls had a 4 auto or 5 manual. Although the cluster matches my 4 cyls exactly...... Hmmmm. I think the but did the 4 cyls have atrac? I doubt it.

 

Lol what??

 

I actually think you are correct. But I am not 100% sure.