Bouncy Bouncy
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Et tu, Madtiger? Say it aint so.
I guess because my BFG KO2 LT-D is in same stock size….and i am at 46 psi all around. Well, with cold weather, it is around 44 psi….but i am too lazy to get out in the cold garage to fix that just yet.
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Thanks all! I have ordered the Firestone Airbags and will up the pressure to 46.
E_
E_
I guess because my BFG KO2 LT-D is in same stock size….and i am at 46 psi all around. Well, with cold weather, it is around 44 psi….but i am too lazy to get out in the cold garage to fix that just yet.
geez man.
You probably know since ive been more active on MUD recently ive extensively beat on my tires with the new brakes.
You know that the load inflation table failed me on my former Ps, calling for 26 PSI. (ridiculous)
As im sitting, 285/70r17 C load, on a top tier tire?
Above 40 PSI cold, i have almost ZERO wet traction. 42 cold, I start to lose DRY traction. Like skidding,... dry...
At least if you want to follow the load inflation table, please for my sake, do two things;
Weigh your rig, and see what the load requirement is for that axles load.
And at the very least do some road tests to ensure your critical tire system is functioning when your going to need it.
46 PSI is out of control high.
I guess because my BFG KO2 LT-D is in same stock size….and i am at 46 psi all around. Well, with cold weather, it is around 44 psi….but i am too lazy to get out in the cold garage to fix that just yet.
Also,
Your LC weighs less than my LX...
At 45 PSI, your tire is rated to hold 2250 lbs. You think your rear axle is loaded up to 4,500 lbs?
Its nonsense trying to convert something from strictly a load perspective, when that defies the very load principle its based on...
Your running a pressure for a truck that is roughly 1,500 lbs heavier than what your LC is actually curbing when fully loaded.
The actual weight on each of your tires is 1,450 lb. unladen. Your almost 60% over that with 46 PSI.
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So what should my PSI be? I am pretty much stock (Except for ARB sliders). 30 psi?
Im just trying to look out for you @Madtiger, the table has its place, but its based on some old facts and has to be used properly.
The table still assumes flotation and LT metric are built differently. Toyo themselves (the authors of the very table being abused) denied any difference but size notation.
g-jin still couldn't accept reality.
The table still assumes flotation and LT metric are built differently. Toyo themselves (the authors of the very table being abused) denied any difference but size notation.
g-jin still couldn't accept reality.
I like my c loads anywhere from 34-36. Your tires even stiffer and shorter sidewalls can probably handle 32 just fine.
I would start to experiment around 36 PSI, plus or minus two PSI tops until you like how it handles and rides.
But test it out, you will see im not s***ting you. Hit a hard corner wet, it will be all over the road 4WD be damned.
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Oh and @Madtiger, watch your PSI in dash.
The way you can confirm its right is to see around a 10% increase from driving.
At 38 PSI cold for example, it should settle around 42 hot after 30 min on highway at 70mph. Any more than that and its heating up too much and needs more.
You should always aim for 10% though, theyre all designed to heat up and work best at operating temp.
Hmmm good idea!!! Thanks.
I've been through this with you before, but it obviously didn't sink in. I'm happy to let you continue with your delusion as long as you don't try to pass it off to others tho their detriment/danger.
You are confusing static weight numbers with dynamic Load numbers - they are very different.
Here is a pic of a LC200 TIP:
There are no tire Load Limit values on there anywhere.
What is on there are STATIC LOAD values for Gross Vehicle Weight (GVWR), and Front and Rear Axles (GAWR). These are STATIC because they are measured on a weigh scale while the vehicle is NOT MOVING.
There is also information on Tire Size (P285/60R18) and Cold Tire Inflation (33psi). This tells us that Toyota has a RCTIP of 33psi for the OEM P285/60R18 tires on a LC200.
Going to the TRA Load/Inflation charts you hate so much, we can determine that the Load Limit for those P285/60R18 tires @33psi is 2,512 lbs.
But hold on a second, if there are two tires per axle that means the total axle Load Limit for the tires is 5,024 lbs! Bu the GAWR is only 3,595 lbs or 4,300 lbs - why have Toyota so wildly overspec'd their tire pressures?
The fact is, they have not! Unlike the STATIC Load of GAWR and GVWR which we can measure on a scale while the vehicle is not moving, the tire Load Limit is a DYNAMIC LOAD value - established when the tire is in motion. Why is it higher than the STATIC LOAD values? Because tires are subject to transient dynamic loading higher than what would be the static load requirement - e.g. hitting a bump, hard braking, cornering, etc.; I'm sure you get the idea.
Let me put it to you another way. Following your logic, the maximum Load Limit the LC200 tires should have would be half the higher GAWR of 4,300 lbs which equals 2,150 lbs per tire, right?
So what does that translate to if we decide to stick with the OEM P285/60R18 tires? It means that you are suggesting (insisting!) that Toyota should have specified something around 24psi instead of 33psi. Not only would this be 2psi lower than the lowest allowable RCTIP for this tire on ANY vehicle, it would be dagerously underinflated for use on the LC200.
So, please. Stop misleading folks with your pseudo-science which leads to false assumptions and dangerous conclusions.
Don't worry, I still have you on ignore
Is it really? Tire Load Limit specifications and RCTIP from Toyota are based on COLD tire pressure. If the RCTIP is 42psi for a COLD tire, it is understood that it would be some higher pressure when in use. Just how much the pressure increases is subject to many variables such as ambient temperature, altitude, barometric pressure, etc. Since it is not possible to control these variables, the RCTIP is set when the tire is COLD. Some increase in pressure with increasing temperature is already factored into the specs - sometimes the increase experienced may indeed be 10%, but it is far from the rule, but rather the exception.
HTH
Ah ok. Thank You very much for explaining!
You're very welcome.
As a bonus, here's a Toyota publication that might help when trying to determine what cold tire pressure one should set when your truck is in a garage and the outside temperature is different - particularly at this time of year:
HTH
Disagree on primarily a shock issue here. Based on my experience with people and stuff in my non-ahc cruiser, it's pretty easy to end up riding the rubber jounce springs, for which no stiffer shocks are going to make much of a difference.
Properly support the load and keep the truck off those rubber bumpers, and it drives just fine. That's why I suggested the 2720s.. near-stock ride height, but higher rate than stock plus progressive so the rate goes up as you add further load.
Properly support the load and keep the truck off those rubber bumpers, and it drives just fine. That's why I suggested the 2720s.. near-stock ride height, but higher rate than stock plus progressive so the rate goes up as you add further load.
I agree and disagree at the same time because there's several ways to look at this.
Bottoming out is one thing, and if we're focused on that, then sure, it can use more spring rate. But I'd wager that even with more spring rate, that with the right bump, it's still very possible to bottom out.
What happens next is all shock.
With enough damping, even a bottom out or g-out event, should not cause further bounce. That's why we spend money on higher end shocks that can generate more damping force. Pair a higher end shock with the stock spring, it may provide enough damping force to manage the compression that things may not bottom out. Even if it did, will provide enough rebound damping force to quell the remaining energy from the compression event.
Add more spring rate while keeping stock shocks... things don't get better.
I see what you’re getting at but “bottom out” has a strange reality on our trucks due to the two different kinds of stops.
The true travel limit stop mounted to the frame rail will present a relatively harsh impact if you manage to get that far by fully compressing the other stop, plus less relevant here but they act to limit tire to wheel well contact on articulation.
The big rubber jounce stop doesn’t take much suspension travel at all to start to engage, and is really the progressive spring of the stock setup. I believe this stop allowed them to run a spring with a low rate with all of the compliance and articulation benefits, while maintaining reasonable load carrying abilities.
Since it is difficult to get a shock configured to progressively dampen in the same way the rate changes with this jounce stop I believe it is better to try and stay off of it during normal use in the first place. More damping can help with large dips and road surface features, sure, but if we are effectively riding on them because the added load has caused a ride height change, those stiffer shocks are still going to be overwhelmed. The rubber parts are just too progressive.
This is one of the few places a lift by itself can really improve ride quality. An extra 2 inches of travel before those stops contact can make a huge difference for moderate loads like OP was faced with. But I wouldn’t tell them to add 2” of rake for this alone, with the negative impact on caster and appearance. More damping definitely won’t hurt, but we need to try and keep the vehicle off those rubber parts and more rate does a better job of this with loads like OP describes, in my experience.
One thing i always thought would be cool for the LC is full air “coils” in the rear, like the GX has.
I don’t think that it’s practical or anything, nor do i know if someone makes them for the 200, but they are cool and would probably work very well for stuff like this.
I wonder if the GX bags are capable enough for a swap.
I don’t think that it’s practical or anything, nor do i know if someone makes them for the 200, but they are cool and would probably work very well for stuff like this.
I wonder if the GX bags are capable enough for a swap.