Odd sensation- It felt like I got rear-ended

Looking for helpful input from the knowledge base here at TW. Any input is welcome.

Technical specifications of vehicle in question:

• 2018 TRD OR regeared to 5.29
• Overland Tailor tune (which is awesome, btw)
  
• Icon 2.5 lift front and rear
• Automatic transmission
• 285/17 wheel tire combo
• Entirely stock drivetrain otherwise

Symptom:
When accelerating hard (like on a highway, trying to get out of the way of a semi), the engine and transmission will continue to pull to slightly above redline.

Not long after 74mph or so, if I keep my foot in the gas (to the floor), the entire truck will buck. HARD. So hard, it feels like I just got rear-ended.

I don't know if the acceleration stops because of a mechanical factor somewhere in the drivetrain, or if I'm so shocked at the sensation that I pull my foot off the pedal. Likely the latter, but either/both are entirely possible.

The first time it happened, I checked my mirrors to see what hit me- it was that violent -and there was nothing there. This is repeatable and has happened around 2 or 3 times.

Resolution:
If it's as simple as "Moron. You have an off road gear setup and are pushing it too hard on a highway", then that's fine. It's a limitation I can live with. If it's something that points to a potential drivetrain issue, I'd like to know that as well.

At the core of the issue, I just want to know what the cause is, and what I should potentially check in the meantime.

Thank you in advance. Let the wild speculation commence!

 

What gear does this happen in?

I've never hit the rev limiter on the taco, but that may be what you are feeling...
It can be dramatic in some vehicles.

Have you considered this?

A low'er' gear, and your re-gear may enhance the dramatic feel.

Just my guess...

 

I did not consider a rev limiter for this. I've hit limiters on motorcycles before and it's never been close to this violent. When I say it felt like I got rear-ended, I mean it. I just don't know what it could be.

 

Rev limiter isn't abrupt in the Tacoma; it just stops accelerating. Found that out the other day getting on the interstate in 2nd gear forgetting to shift into 3rd. It was pretty darn peppy in those RPM ranges...

 

Fuel starvation or a sudden loss of spark. You have a 2018, so fuel pump would be the first culprit.

 

I've noticed a couple times when I come to a stop I get a little bit of a jolt, I believe it comes from fuel in the gas tank splashing around.

 

I mean... you are pushing it way too hard....
To me, getting kicked in the ass leads me to think its the transmission being indecisive/ gear slip. Getting kicked in the chest would be indicative of engine starvation. Either way, its probably reducing the lifespan of your drivetrain.


"Doctor, it hurts when I do this."
"Then stop doing that."

 

That's some abusive acceleration brother! No wonder your truck is behaving strangely. I feel for the poor bastard who buys this truck when you are done with it.

 

I never put my foot to the floor because I'm in a truck and not a sports car.... YMMV....

 

Since you have an auto and a tune, it’s probably shifting up near redline too aggressively and/or locking the torque converter at a strange time.

 

I am curious about this. I find that I don't need to use full throttle. - I've never been there on the taco. I haven't even done that in my sport car days...
I don't drag race and I've never been in such a hurry...

 

Yeah I'm in a lifted real high taco on 35's automatic with no regear and have never felt like I needed more power or have ever had to put my foot to the floor. I think from reading on this forum the 3.5 needs a re-gear for more low down power if you lift and do big tires though.