Has anyone’s warranty been voided by using a JB4?

I want to install a JB4 on my ‘23 hybrid, but I’m chicken because I’m worried about denial of any warranty work.
Any advice, comments, suggestions, concerns?

 

The JB4 will not necessarily void warranty .If there is a failure or a part that could be attributed to the aftermarket device, that warranty claim could well be denied

 

I've read at other threads that dealership can run reports on their computer and see if the components of the engine were working too hard, out of spec - and therefore they will make a conclusion that you used an aftermarket device to make components work harder than they should have. And then then can deny your warranty coverage. (e.g won't replace your engine or turbos)

 

An experienced mechanic that knows how to read freeze frame data can possibly figure out that a tuner has been connected when the failure occurred . I’m not certain that they’ll catch it but it definitely is possible

 

Assuming data is recorded when the vehicle is driven and they can access the data, they can see timing, boost, and more, they will be able to tell if you have a tuner involved in the whole process.

 

Haven't heard of it happening. I've taken mine off when it's been in for service though...no need to risk it

 

Except the JB4 spoofs the pcm into thinking its making less boost than it is. So as far as the pcm knows, nothing is different

 

They would have to dig really deep and somehow infer it from Fuel trims or wastegate duty cycle. The pcm doesnt know the engine is getting more boost with the jb4

 

If you need to replace the engine or the transmissions, I would expect Toyota to pull controller data. There will be more than enough there to deny the warranty.

Other forums with vehicles that the JB4 is more common on do have people bitching about denied warranties after knowingly or unknowingly trying to commit fraud. I would not expect Toyota to be any different, particularly when their reliability numbers mean they can pay more attention to serious failures.

 

I had the JB4 on my 2022 3.0 Supra, it leaves a trace of course. This isn’t the old days where you rip it off and computers don’t record that info, they do. If you use a JB4, I’d highly recommend someone tune it for you. I know certain Maps when used for Supra’s were blowing turbos, would hate to see that.

 

At least not yet. I have the 1794 hybrid and feel like it have more than enough power/torque for a truck. I wouldn’t risk it for a little bit of gain, not like you can race with a half ton anyway

 

If you can’t afford to pay for a new engine, transmission, transfer case, or other driveline hardware out of pocket; then you can’t afford to use a tuner on your new truck. At least while under warranty.

Pretty simple concept.

If you need or want a more powerful, more capable truck buy one that is already more powerful and more capable. There’s a bunch of options out there for trucks that pretty thoroughly outperform the Tundra in a variety of ways if you need more power or capability. I have a tough time understanding why so many guys want to try to make their 1/2 ton Toyota Tundra into something it will never be.

1.) The Tundra is not a race car. You could spend $5,000 on go faster parts, labor, and tuning for your Tundra and still get your dick kicked in at a stoplight by a new 5.0 Mustang GT with an automatic transmission driven by a 17 year old. All you’ve done is made your slow truck marginally less slow in the grand scheme of things.

2.) The Tundra is not a heavy duty truck. No amount of tuners, air bags, heavier springs, or other bandaids is going to put it on par with a 3/4 ton HD gasser…. much less a diesel. Buy a bigger truck.

 

Those of you concerned over warranty denial should brush up your incantation and arcane knowledge skills.








(tee hee!)

 

So Toyota technicians can dig through computer data models but can’t replicate wind noise

 

JC, you must be a blast to hang out with.

You must of missed that there is an entire aftermarket to enhance just about every performance aspect of almost every vehicle. Going beyond what a manufacturer deemed “enough’
Or perhaps they just didn’t get your memo

 

LOL, I might be a bit harsh on this one.

I’m all for modifying vehicles to maximize the core functional attributes where it makes sense. Make an already fast car faster etc.

Pickup trucks though? Adding a few HP at the very real expense of voiding factory powertrain warranty is a juice not worth the squeeze. The reward of a slightly less slow truck isn’t worth the risk in my estimation.

 

I’ll bet the dealer tech will not be the one digging on a warranty claim for a blown up engine or transmission.

In the event they are the ones digging their motivation to do so might be higher because non warranty work is going to pay them more than warranty work in most cases.

 

Perhaps I was too.
I agree that modifying a car to do something it wasn't designed to do is a fool's errand. Particularly if one complains about the outcome.
But adding a bit more hp to enhance the fun factor? Have at it.
Is it worth voiding the warranty? That's the OP's call

 

That’s the big problem for me, and why I leave vehicles stock under warranty.

Plus leaving the daily driver alone aside from regular maintenance for max reliability is usually wise.

Project car/truck or toy? Play to your heart and wallet’s content!

 

This isn’t that hard to think through . If you add tuner then also be ready if the dealer denies claim for whatever if you have modified said system . I mean if you buy an iPhone and you crack it open to modify you can’t expect it to be surprised if they deny your claim later .
I think it would be quite easy as a Toyota engineer to prove the program has been changed . Lots of clues within one freeze frame that could indicate tampering . Boost value ain’t the only one but you could get lucky and get the tech that don’t care

 

My 17 4Runner had a complete brake system failure while I was driving. On local road at 30 MPH. Coming up to Stop sign-Brake pedal goes to the floor and no stop. Pucker factor immediately maxed out. Started pumping the pedal for very marginal brakes and applied E-brake. Got it stopped middle of 4 point intersection and fortunate no car in front of me or at the other points. Anytime you applied brakes, the pedal went to the floor. Toyota picked it up on a flatbed and took it dealer. Brakes were completely out when we rolled it into the bay. Tech shut it down, hooked it up to the diagnostic and behold, now brakes fully functional. Toyota after a full diagnostic told me could not replicate and wanted me to pick up and drive it. I refused. Took about a month and finally the region senior tech arrives with computer. We drove the truck for 50 miles on the interstate, local roads, in 4x4 and brakes worked fine. I dug in and told them I am not taking the truck back and figure out what happened. At this point, they pull it back into the service bay and sync the truck OBD with some mainframe location and complete a full dump of stored data. They then asked me date and time of incident. They found it and it showed complete brake loss and the brake pumping by me within some deep records stored within the OBD system. Very politely told them--your initially denied the event occurred. Imagine me driving this and being behind you or a family member when it happened again. Fix the problem and not band aide it or your next correspondence from me would be via my legal counsel. The brake system and all components were replaced. Anyone doubt this, go over to the 4Runner site and its fully documented there when it happened.

So the long answer to your short question, yes then can find a lot via OBD Computer records.

 

Wow, that is nuts.

 

Crazy, glad you and others on the road were ok.

 

You would be amazed at the data we can pull up with Techstream in these newer trucks. The computer logs many things, harsh acceleration, shifting too fast from reverse to drive, abs operation, etc.

With that being said if somethings spoofing the computer to think a value is reading less than it really is, I dont think we’d pick that up directly, but through all the other PIDS the guys in Texas we send the files to on warranty jobs could likely pickup “something third party is messing with something”

 

Exactly. Like via harsh acceleration maybe. Or wastegate duty cycle, or something else.

Youd have to know what ur looking for though

 

Especially with them being new new, any engine or transmission failure will most likely require a TAS case. If it does they’ll want Techstream data and Texas will go over it all with a fine tooth comb

 

Terrifying. But good on you for sticking to your guns. Solid reminder that safety puts us in a position to demand techs to do their jobs, regardless of what they say.