I might have to take you up on that. I haven't ordered parts yet but if you're cool with it sometime in probably late jan or feb when they would come in i'm game.
The FK fuel tank thread…
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Yeah i figured that. It's just hard for me to justify that much when i can do it myself just lack the lift. And having just did 3 tank/sending unit swaps in my old ranch truck on my back, i'm just not here for it anymore.
I like Duggy's and use them for suspension projects without regret. When they quote me $3,500 installed for a set of Slee sliders on my 200 when the parts are a shade less than $2k delivered, I get to wrenching.
seems like aux tanks and sliders are not what they want to do.
I was going to say ... have heard good things about the shop there, no personal experience, but $1500 to install sliders suggests they don't want to do that install.seems like aux tanks and sliders are not what they want to do.
I sold my LX570 but can understand, if the install was for that version of the LC200, not wanting to mess with it if the AHC lines needed work or relocation in the process (don't recall what is involved in the Slee slider installation for the LX570).
Similar thing in the Land Rover Defender world I delved into - shop quoted 6-9 months wait to install an admittedly complex subframe / body lift (L663 Defenders are a unibody). Between the cost of the 'lift', cost of the install, and wait, I decided to pass. Cost aside, knowing the shop just didn't want to mess with it was an equally big deterrent.
But back to the topic at hand, big thanks to the OP for pioneering this path. The factory range on the Overtrail killed it for me when I was shopping for a new vehicle earlier this summer. You've given me a reason to take another look though
. (Edit for autocorrect correction)
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They just want that gravy work. Not goodI was going to say ... have heard good things about the shop there, no personal experience, but $1500 to install sliders suggests they don't want to do that install.
I sold my LX570 but can understand, if the install was for that version of the LC200, not wanting to mess with it if the AHC lines needed work or relocation in the process (don't recall what is involved in the Slee slider installation for the LX570).
Similar thing in the Land Rover Defender world I delved into - shop quoted 6-9 months wait to install an admittedly complex subframe / body lift (L663 Defenders are a unibody). Between the cost of the 'lift', cost of the install, and wait, I decided to pass. Cost aside, knowing the shop just didn't want to mess with it was an equally big deterrent.
But back to the topic at hand, big thanks to the OP for pioneering this path. The factory range on the Overtrain killed it for me when I was shopping for a new vehicle earlier this summer. You've given me a reason to take another look though
EscapeWagon62
SILVER Star
In progress
Hope to pick up Monday
Hope to pick up Monday
EscapeWagon62
SILVER Star
Installation was flawless. Mine is just adding an aux tank.
UPDATE - if you are doing an LX600 it cones with the fuel pump housing assembly such that you do not have to make any modification (like you'll see in FK's LX700 video where you have to snip out part of the housing)
So if you have an LX600 there are zero modifications to the vehicle and if you ever want to revert to taking out your aux tank, it's simple.
UPDATE - if you are doing an LX600 it cones with the fuel pump housing assembly such that you do not have to make any modification (like you'll see in FK's LX700 video where you have to snip out part of the housing)
So if you have an LX600 there are zero modifications to the vehicle and if you ever want to revert to taking out your aux tank, it's simple.
I am in Saudi Arabia and have been in touch with FK Industries. The folks have been very helpful and quick response time. They were able to connect me with one of their customers who is also in Saudi.
The guy has an LX700H and did the 110L main and 54L sub swaps. He was very helpful and gave me the number of the workshop that did the installation. I just spoke to the workshop owner and he agreed to do the installation.
Let's hope the LC300 GR-S hybrid works like the LX700H. Seems very similar.
Now for the tricky part, securing the funds
Will share an update once I put the order in.
Sharing pics for reference
The guy has an LX700H and did the 110L main and 54L sub swaps. He was very helpful and gave me the number of the workshop that did the installation. I just spoke to the workshop owner and he agreed to do the installation.
Let's hope the LC300 GR-S hybrid works like the LX700H. Seems very similar.
Now for the tricky part, securing the funds
Will share an update once I put the order in.
Sharing pics for reference
EscapeWagon62
SILVER Star
So I’m a couple of weeks into having my 600 Aux tank installed.
Flawless.
My only issue is that I didn’t note how many miles I’d driven and my fuels gauge was still showing full (some fear my gas gauge was stuck….self inflicted worry)
My observation is that as the Aux tank gets near empty, your gas gauge will wobble between 100% and 90% until the aux tank is fully empty….then it goes down as normal.
Refilled today as I’m heading off on a trip. Zero change in fill up as it seamlessly fills both tanks at once.
Get used to seeing three digit gas bills
I set the trip meter to see how many miles before gas light comes on.
Flawless.
My only issue is that I didn’t note how many miles I’d driven and my fuels gauge was still showing full (some fear my gas gauge was stuck….self inflicted worry)
My observation is that as the Aux tank gets near empty, your gas gauge will wobble between 100% and 90% until the aux tank is fully empty….then it goes down as normal.
Refilled today as I’m heading off on a trip. Zero change in fill up as it seamlessly fills both tanks at once.
Get used to seeing three digit gas bills
I set the trip meter to see how many miles before gas light comes on.
EscapeWagon62
SILVER Star
PROBLEM!
I’ll cross post this to the Auxiliary Fuel Tank for the space under the LX600
Driving down the freeway today I got a check engine light “parking assist inop” warning message (which toyota seems to use as a default in many models)
Total luck - I was two exits away from my Lexus store and they agreed to let me roll in at 4:55pm
Bad luck - The fault is due to fuel level mismarch based on miles driven. Also of note…I have 326 miles since fillup, averaging 18.4 MPG and the gas gauge is still pegged above full (I should be well into the main tank at this point)
I’ll readh out to FK
Has anyone else already experienced this and knows of a solution.
Error readout and fuel/trip/gauge photos attached.
I’ll cross post this to the Auxiliary Fuel Tank for the space under the LX600
Driving down the freeway today I got a check engine light “parking assist inop” warning message (which toyota seems to use as a default in many models)
Total luck - I was two exits away from my Lexus store and they agreed to let me roll in at 4:55pm
Bad luck - The fault is due to fuel level mismarch based on miles driven. Also of note…I have 326 miles since fillup, averaging 18.4 MPG and the gas gauge is still pegged above full (I should be well into the main tank at this point)
I’ll readh out to FK
Has anyone else already experienced this and knows of a solution.
Error readout and fuel/trip/gauge photos attached.
EscapeWagon62
SILVER Star
No solution but did receive a timely response.
I will follow up with my tech at Lexus.
I’m going to drive it some additional miles to see if my gas gauge starts coming down (which is more of a concern to me than check engine as of today)
FK Note back on my inquiry:
Yes, we have encountered this issue before.
Based on our analysis and real-world testing, the root cause is related to the auxiliary tank’s fuel transfer behavior. During driving, the auxiliary tank continuously supplies fuel to the main tank, which causes the fuel level in the main tank to remain nearly unchanged for an extended period of time.
This is exactly where the issue originates. From the LX600 ECU’s perspective, a stable fuel level despite ongoing fuel consumption is considered abnormal. After several driving and calculation cycles, the ECU may trigger a diagnostic trouble code such as P0460.
At this stage, we have observed that this phenomenon is specific to certain models, most notably the LX600 and GX550, after the installation of an auxiliary fuel tank.
In summary, the root cause is:
the fuel level float in the main tank remains within a very narrow movement range for a prolonged period, even though fuel is being consumed.
Our currently discussed solution option is:
Please feel free to let us know if there is anything we can assist with. We are happy to provide any available technical support or further clarification.
I will follow up with my tech at Lexus.
I’m going to drive it some additional miles to see if my gas gauge starts coming down (which is more of a concern to me than check engine as of today)
FK Note back on my inquiry:
Yes, we have encountered this issue before.
Based on our analysis and real-world testing, the root cause is related to the auxiliary tank’s fuel transfer behavior. During driving, the auxiliary tank continuously supplies fuel to the main tank, which causes the fuel level in the main tank to remain nearly unchanged for an extended period of time.
This is exactly where the issue originates. From the LX600 ECU’s perspective, a stable fuel level despite ongoing fuel consumption is considered abnormal. After several driving and calculation cycles, the ECU may trigger a diagnostic trouble code such as P0460.
At this stage, we have observed that this phenomenon is specific to certain models, most notably the LX600 and GX550, after the installation of an auxiliary fuel tank.
In summary, the root cause is:
the fuel level float in the main tank remains within a very narrow movement range for a prolonged period, even though fuel is being consumed.
Our currently discussed solution option is:
- Masking or disabling the P0460 diagnostic trouble code. This approach is sometimes used in China in similar scenarios. However, we would like to better understand whether this solution is compliant with U.S. regulations, or whether this method is used in practice by installers or off-road specialists in the U.S. market.
Please feel free to let us know if there is anything we can assist with. We are happy to provide any available technical support or further clarification.
It is a good thing they know about the issue.
Not so good that they do not appear to have a solution for it (other than disabling the code, which is at best questionable) and are kinda asking you for your thoughts?
Not sure if they did, but I would also fully expect them to disclose this potential issue to me BEFORE I moved ahead with the purchase, so I could decide for myself if I wanted to run the risk of having a CEL on all the time while running the truck - this is always a risk since you would never know about other problems happening with the truck once the light is always on because of the aux fuel tank misreading issue.
I am rooting for you and hope you find a solution.
EscapeWagon62
SILVER Star
Well, I expected some quirkiness going aftermarket. I’ll find out more as I dig in. It would not bother me greatly to mute/disable a specific code but over on the other thread Oakley brings up some potential work arounds.
As for the trip when the CEL code came on……
Installed tank
Filled up
Ran through the entire aux and half the main
Filled up and drove some 240 miles round trip with a 6 day break half way through (parked at airport)with no issue
Drove 25 miles, parked for 6 hours, driving back home and light came on.
It may or may not be that my float is actually stuck right now. I haven’t dropped below full. Over the course of the next few days I’ll know if its stuck or not.
If not…..won’t bother me a bit to suppress the CEL code.
As for FK - they are lightening fast on response time (accounting for time change relative to China)
The engineering is solid and I’m somewhat understanding of the fact that these bolt ons may have effects on other systems which are unintended.
As for the trip when the CEL code came on……
Installed tank
Filled up
Ran through the entire aux and half the main
Filled up and drove some 240 miles round trip with a 6 day break half way through (parked at airport)with no issue
Drove 25 miles, parked for 6 hours, driving back home and light came on.
It may or may not be that my float is actually stuck right now. I haven’t dropped below full. Over the course of the next few days I’ll know if its stuck or not.
If not…..won’t bother me a bit to suppress the CEL code.
As for FK - they are lightening fast on response time (accounting for time change relative to China)
The engineering is solid and I’m somewhat understanding of the fact that these bolt ons may have effects on other systems which are unintended.
EscapeWagon62
SILVER Star
Good news - Updates and info (I'll cross post to the Aux tank for the open space under the LX600 thread as well)
OK, here is what I'm seeing.
1. Gas gauge
4. How am I feeling overall?
OK, here is what I'm seeing.
1. Gas gauge
- It's working - we can chalk this up to "gauge anxiety" but I did learn more about how it's functioning
- The fuel sender unit in the main tank is from FK.
- It seems to be biased towards full (shows above full at max) which gives the impression that it's stuck on full when in fact it is not.
- My gauge stayed above full, then to full and started dropping at ~360 miles (at 18.2 MPG avg) and then started to come down as normal. I've had vehicles in the past that can be full biased or empty biased. Now that I know how this one operates I'm fine.
- It was cleared easily
- In the USA, Lexus dealerships are not given access to mute or suppress codes nor would it be legal for them to do it if they did have access
- I'll have to buy a $30 OBDII tool to clear a code if it comes back.
- According to my techs, it is LIKELY that the CELs will stop as these systems are smart and always learning. It should (not guaranteed) realize over time that the vehicle is functioning normally.
- As I mentioned in an earlier post, the gas gauge wobbled a bit when transitioning form the Aux tank to the main tank.
- My bet is that this wobble as it sucked the last gas from the AUX was what caused the system to flag it as this was right around the mileage I'd expect the Aux tank to be emptying.
4. How am I feeling overall?
- I'd do it all over again in a heartbeat.
- I'll get about 630 miles out of one fill up (maybe more with freeway only)
- Do I wish I didn't throw a CEL? Yes but for $30 I'm not too concerned.
- Now that I know the behavior of the gas gauge/sending unit I won't have gauge anxiety anymore
- FK's customer support response time and willingness to help address issues is solid.
- I may end up ordering an extra fuel sending unit from FK as it's the only significant operational item (the others being hoses and the physical tank) that are not OEM at this point. Having a spare may be in my future just in case
- There are folks on this forum plus my technicians who are thinking about ways to get combined tank level readings. I'll just watch and see if anything solid comes along.