Cool, looking forward to updating, thank you!
VF Tuner ECU/TCU Tuning for the GX550 (1 Viewer)
- Thread starter VF Tuner
- Start date
I wanted to comment about an issue with the low speed drivability and if your tune has fixed what I am experiencing @VF Tuner
When slowing down to a near stop then getting back on the throttle, there is a massive (nearly 2 second) delay in acceleration before the truck figures out what to do. Most of the time it will eventually downshift into 1st gear then finally begin to take off. This can be replicated in any of the driving modes 100% of the time and does not matter if the truck is cold vs. warmed up. This is without a doubt the most annoying thing about the truck and I really hate to say it .. but I would gladly pay for a tune to fix this because I love the truck otherwise.
Late 2025 Overtrail build, 4,000 miles.
When slowing down to a near stop then getting back on the throttle, there is a massive (nearly 2 second) delay in acceleration before the truck figures out what to do. Most of the time it will eventually downshift into 1st gear then finally begin to take off. This can be replicated in any of the driving modes 100% of the time and does not matter if the truck is cold vs. warmed up. This is without a doubt the most annoying thing about the truck and I really hate to say it .. but I would gladly pay for a tune to fix this because I love the truck otherwise.
Late 2025 Overtrail build, 4,000 miles.
Not sure if you are referring to the clunk issue when coming to a stop or not, but I am not experiencing any clunk whatsoever. My issue is more of a throttle lag / delay.
I did a quick search and found a similar thread actually:
Low Speed Shifting
Picked up a new 2025 OT two weeks ago and currently have about 600 miles on it. Mostly love everything about it so far except for one thing. When slowing down to a crawl/slow roll, and trying to speed up, it feels like the transmission stays in too high of a gear and is not ready to...
www.lexusgxforum.com
Have you experienced this firsthand before writing any tunes to customers cars? Does your tune change any throttle mapping?
I noticed this immediately when I drove the truck. It can be sort of helped by easing into the throttle. I have purchased the VFTune, but haven’t flashed it yet. I’m hoping that will help. The long lag time is super annoying and slightly dangerous when trying to pull out in traffic.
I'm back and ready to make the switch to this tune. I read through the entire thread including the unnecessary entertainment! I just reached out to VF this morning with a list of questions. I apologize and should have read the thread first since I found many answers scattered here. My GX does have AFE intakes and charge pipes ... It seems like @munkeeboi may have the same setup. (let me know if you have any issues).
Does the v2 transmission tune address slow shifting? I haven't seen any updates on a TSB for that.
How much ethanol can be run on stock fuel pump?
When is the iphone flashing ability coming? Is it worth waiting for that release or will everyone gain that ability?
Does the v2 transmission tune address slow shifting? I haven't seen any updates on a TSB for that.
How much ethanol can be run on stock fuel pump?
When is the iphone flashing ability coming? Is it worth waiting for that release or will everyone gain that ability?
- Thread starter
- #429
phone flashing / phone logging will be a free update.
there has been at leas 1 or 2 reports of some folks having issues with the AFE Intakes, but the cause was never determined (as far as I know).
I want to apologize for our missed previous deadline. We want this new version tune to be perfect for you guys and a little bit of test data is coming in slower, but if you want to test it and provide us feedback send us over an email
I have the AFE intakes but not the charge pipes. I have had zero issues with just the intake while people have had issue with the charge pipe even without a tune. Waiting for VF Tuners charge pipes.
Disclaimer that I don’t floor my GX so your results may vary depending on how you drive. It seems most issues have arisen from people pushing their AFE equipped GX’s. I have other cars to drive if I want to go fast.
This video shows the issue with the AFE charge pipes. There is a thread for it. I plastic welded the hose barbs on mine so they won’t pull out.
Here is a link to that thread.
www.lexusgxforum.com
Afe intakes/inlets with VF tuner tune
Hello everyone, I recently got my GX 550 tuned with the VF tuner 93 OTS v3 tune. My issue is I was already running AFe intakes and inlet pipes. The extra airflow is most likely what is causing my misfire/check engine light because the VF tune is designed for a stock car. I already reached...
www.lexusgxforum.com
I see I was not the only one with aFe issues. I'm maxecutive from youtube. Lot's of recent life events kept me from posting recently... I just hit 17k miles and haven't had a single CEL since I took off their scorcher unit. The intakes and charge pipes are still there without an issue for the last 7k with their update barb fitting.
The video with the red intake pipes demonstrates the problem nicely. The check engine light was always for that hose. If it becomes problematic again, I can always swap to VF.
The video with the red intake pipes demonstrates the problem nicely. The check engine light was always for that hose. If it becomes problematic again, I can always swap to VF.
- Thread starter
- #434
A few updates for you guys.
We are working on a significant update for Load/Boost control, as toyota (lexus, same thing) has implemented a few additional load limiters that strip out boost if you increase it, on these latest ECU versions (actually if you increase boost past a certain point it defaults to "lowest possible boost, about 5psi)
This will be resolved very soon, and our updated tunes roll out to everyone.
We thought we had it all finished but testing is still in progress to wrap up this huge tune update.
Finally, pre-order pricing on our upgraded turbos ends in 9 days.
We are working on a significant update for Load/Boost control, as toyota (lexus, same thing) has implemented a few additional load limiters that strip out boost if you increase it, on these latest ECU versions (actually if you increase boost past a certain point it defaults to "lowest possible boost, about 5psi)
This will be resolved very soon, and our updated tunes roll out to everyone.
We thought we had it all finished but testing is still in progress to wrap up this huge tune update.
Finally, pre-order pricing on our upgraded turbos ends in 9 days.
Looking forward to the update - I will likely order a kit when your revision is complete.
GX550 Forum Photos
GX550 Forum Photos
