It's time for me to replace the stock tires on my CRD. My rig is still stock and that's the way it will remain for the foreseeable future. I use it mainly on road (to and from work) and occasional light off road work (fishing and hiking trips etc.). If I get around to buying a boat (20' or less), then I'll want to use the CRD to pull it. Good wet weather and snow capabilities are also a must. Road noise and ride are secondary concerns - but there are still concerns.

I pretty much want to stick to the stock tire size, or as close to it as possible.

Revos seem to come highly recommended for my intended use.

The question that I'm trying try to resolve is what size tire should I go with?

They do make a Revo in the stock size of 225/75R16, but it's an LT-Metric tire, not a P-Metric. This offers some advantages - i.e. higher load rating, but may also comes with a few drawbacks i.e. higher required tire pressure, rougher ride (anybody have any input on the ride difference?) etc. The LT tires are also more expensive and don't seem to have a warranty.

The P-Metric 235/70R16’s have the same contact patch width, a larger section width (0.7" greater), but are 1/2" less in diameter than the 225/75R16's. The P-Metric 245/70R16’s have a larger contact patch than stock (0.3" greater), a section width that is 1" greater, and a diameter that is equal to the stock 225/75R16's. The P-metric sizes all come with warranties.

So what should I go with?

Again my desire is to stay as close to stock as possible. However, right now I'm inclined to go with the P245/70R16's.

Go with your inclination!

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Slightly modified Lt. Khaki 3.7 2004 LTD 4X4. Purchased new 8/6/03.
What I don't have....A Mag light mounted to my seat.
Original Old L.O.S.T. #000354

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245/70/16 is what I chose (over the protest of the tire dealer) and don't regret the choice. You will get virtually identical overall diameter & rev/mile as the stock 225/75/16. You will also get the same weight capacity as stock (235/70/16 is down 1 weight class) with lower required air pressures (44psi vs 50psi) to achieve max weight capacity. The difference in weight capacity is important on the front of the CRD. Even with only 32 psi, the front tires don't look like they are going flat (like the stock tires with 40psi). The difference in high-speed stability was like night and day compared the the stock tire. Thus far very happy with the Destination LE.

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2005 Liberty Sport CRD, Lt Khaki, sunroof

Thankful to now be an EX-CRD owner.

with those 3 tires it will make very very little differance
one is wider one is taller but by such a small amount you wont notice it as far as prefomance
as far as load range I would look for one that had a C range D at the max the higher the load range the heaver the tire as well as the worse it will ride
remember that most C range tires will hold around 2K lbs each that gives you 8000 lbs of tire wich is way more than your KJ will ever weigh
and the heavy tires will cost you mpg even with a CRD
and the tire comes with a warranty but it will depend on where you buy it from if you buy it local and for some reason a belt breaks in one getting it replaced will be much easier then if you mail order
I have E range revo's on my F250 they have a warranty if I dont have a load they ride like poo poo and if I drive it all day and park it when they are hot when they cool over night they have flat spots in the AM

hope this helps

My two questions are 1) What issues, or how appropriate would LT-metric tires be for this application? 2) Are there any issues with the addtional section width of the 245/70R16's?

In regards to number 1 - The higher tire pressure and load rating suggest they may not ride well. Other issues?

In terms of number of 2 - From what I've read the additional width doesn't result in rubbing issues etc. Other issues?

P245/70R16's still seem like the most likely choice.

I bought traction tires (Bridgestone Dueler A/T) for the rear of my Chevy pick-up and went with an "LT" over a "P" size. They are definately firmer but don't turn squirley when I drop 1000+ lbs. in the bed.

It's a matter of personal choice and application, the higher pressure & narrow tire will give you better highway mileage. My needs are for traction on snow & ice where the ability to run on the soft side is usually beneficial. The wider tire provides that capacity.

As for the extra section width on the CRD, Not seeing any rubbing issues with the 245/70.

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2005 Liberty Sport CRD, Lt Khaki, sunroof

Thankful to now be an EX-CRD owner.

#1 you don need to run tires at the marked psi the tires on my kj are marked 50psi I run 32 and thats fine for a lower load range tire
if you put a D or E range tire you will find that it is rated for around 70psi and and 3-4K lbs each wich if you only put ~30psi and it sits will cause "flat spots"
and a realy crapy ride
you keep refering to LT and P metric sizes that is not the tell all if you go LT you will need to look for the load range as well

#2 the width can cause rubbing at some point the thing to remember about width vs hight is that when you turn your wheel the inside edge moves out and the outside edge moves in if you draw a line fromthe rear outer side wall through the canter to the front outter side wall that is the number that will tell you how width will cause rubbing
I know that a 245/75R16 MT/R will fit on most lifted rigs with no rubbing and has the same OD as a 31X12.5 BFG MT but the BFG will rub like crazy

The size that you are looking at SHOULD work but my '03 settled way down and I think that had I tryed to run the 245/70's they would have rubbed

I'm not sure that I'm following you here... Regardless I'd offer a word of caution concerning LT tire pressures, especially when going from P-metric to LT-metric tires.

The basic rule is that LT-metric tires require (significantly) more air pressure to handle the same load rating as their P-metric counterparts. Running LT-metric tires at similar pressures as P-metric tires can lead to excessive heat build up - compromising durability and safety. See this Nitto Tire link:

http://www.nittotire.com/assets/safety/Replacing%20Tires%20on%20Light%20Trucks.pdf

Here is another link from Yokohama that imparts similar information:

http://www.yokohamatire.com/pdf/tsb-070302.pdf

Take the case of replacing a P225/75R16 tire with a LT225/75R16 tire. According to Bridgestone, the P225/75/R16 tire has a load capacity of 1911 lbs @ 33 PSI. To achieve the same load capacity with a LT225/75R16 you have to run it with 50 PSI (1940 LBS @ 50 PSI). Also note that this is the maximum load range for a C load rating. See the Bridgestone link for further information - note the tables at the bottom:

http://www.tiresafety.com/images/Tire%20Replacement%20Manual.pdf

Factoring all that in - to get the Revo's in LT225/75R16D, I would have to run them at significantly higher pressure. The end result, I suspect, would be poorer ride quality. LT tires also tend to generate more rolling resistance and therefore they decrease economy. However, they are the right size. How severe of an impact would the above mentioned negatives have? Well I can't be for sure...

Given the above... It seems to me that a P-Metric would be better suited for this application. That leaves the P235/70R16 and the P245/70R16.



That thought has crossed my mind. Over time the front end might start to sag. I wondered if any clearance issues would begin to creep up with P245/70R16's. I doubt it, but the thought crossed my mind anyway...

I'm not sure that I'm following you here... Regardless I'd offer a word of caution concerning LT tire pressures, especially when going from P-metric to LT-metric tires.

The basic rule is that LT-metric tires require (significantly) more air pressure to handle the same load rating as their P-metric counterparts. Running LT-metric tires at similar pressures as P-metric tires can lead to excessive heat build up - compromising durability and safety. See this Nitto Tire link:

http://www.nittotire.com/assets/safety/Replacing%20Tires%20on%20Light%20Trucks.pdf

Here is another link from Yokohama that imparts similar information:

http://www.yokohamatire.com/pdf/tsb-070302.pdf

Take the case of replacing a P225/75R16 tire with a LT225/75R16 tire. According to Bridgestone, the P225/75/R16 tire has a load capacity of 1911 lbs @ 33 PSI. To achieve the same load capacity with a LT225/75R16 you have to run it with 50 PSI (1940 LBS @ 50 PSI). Also note that this is the maximum load range for a C load rating. See the Bridgestone link for further information - note the tables at the bottom:

http://www.tiresafety.com/images/Tire%20Replacement%20Manual.pdf

Factoring all that in - to get the Revo's in LT225/75R16D, I would have to run them at significantly higher pressure. The end result, I suspect, would be poorer ride quality. LT tires also tend to generate more rolling resistance and therefore they decrease economy. However, they are the right size. How severe of an impact would the above mentioned negatives have? Well I can't be for sure...

Given the above... It seems to me that a P-Metric would be better suited for this application. That leaves the P235/70R16 and the P245/70R16.



All that is very true if you were running them at 1800# or more per tire but you will NEVER put that much on a tire on a KJ at least not running down the Interstate and for the times that you do lift a wheel it would be fine

I have weighed my KJ ,3.7 gas, at it seems very very well balanced at about 1000-1250# per tire ,I work for a company that specializes in scales and weighing systems and I used 1 scale per wheel
I know that the CRD weighs more maby even 500# or more but I doubt tht all of that is on the front alone

knowing that you have maby 75% of that tires cap on it and friction builds heat to run a tire that can hold 1900# at less air is OK
I do it all the time and have done it on the past 4 4X4's that I have owned I have never had any problems on the road only when I cach a side wall on something on the trail but I would rather chance it on the trail then spend way more $$$$ and have a crappy highway ride

do what you feel safe with but I would not put a tire on a rig if I need to push it to the max just to run down the highway
when you air down for the trail you will blow beads like crazy

I must have jumped into a parallel world as I am agreeing with Mr. Thompson.

The tires that came with my Libby had a load rating of 960#. When I switched to the Revos (I went with the P245/70's) I guess that according to T2's calculations I could have run them safely at about 20# as they almost have a load range that is double the OEM tires.

In all seriousness the P-metric tires were more than adequate for most driving conditions that I encountered. I towed small boats with them, went on challenging trail rides and took on all kinds of treacherous weather conditions. The tires handled it all in stride. Changing the tires to the Revos was the most important upgrade that I have done to the Libby. Not only do they work great in the ice and snow but they also give a huge improvement in handling.

Now I am running the Goodyear MT/r's in a LT245/75 r16. These have a load range of E and could probably be used as replacement tires for a small dump truck. The ride is a little more harsh than before but I feel more confident when I am driving in new construction sites with about 600# of tools and material in the back.

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Tarkus is So Lost#000345
KJ Expeditionary Group
31" MT/R's and Rustys lift

I've made no calculations. The numbers I used were quoted from tables in Bridgestone's material. How you came up with a 20 lbs figure I don't know. Here's all that I said - The P-Metric OEM tire has a load capacity of around 1911 lbs @ 33 PSI. To get the same load capacity from a LT-Metric tire you have to run it at approximately 50 PSI. The OEM Goodyear Wrangler ST's actually have a maximum load rating of 1984 lbs @ 35 PSI (similar to the Revos). I don't know where you get 960 lbs. The curb weight of the Diesel Liberty is approximately 4300 lbs. Assuming an even weight distribution - a 960 lbs load capacity would be inadequate even before the driver gets into the vehicle.

The GAWR of the Diesel Liberty is 3150 lbs in the rear. Assuming the vehicle has been loaded to this limit (combination of passengers, cargo, or tongue weight not to exceed 1150 lbs) and the weight is evenly distributed, the resultant weight on each tire would be somewhere around 1575 lbs. A LT225/75R16 tire @ 35 PSI has a load capacity of 1500 lbs. This is why I would be weary of trying to run an LT-metric at P-metric tire pressures. Factoring the worst case scenario as the best approach - it seems most desirable to have the 400+ additional lb capacity, or safety margin, of the OEM tire pressure specifications. It seems especially so when you consider that these figure are all taken at rest. What additional weight gets put on an individual tire when you consider things like uneven weight distribution and the weight shifting/additional forces a tire may experience during maneuvering?

Again my point being is that as a rule you need more air pressure in an LT-metric to get the same load capacity of a P-metric, even though the LT-metric generally has a higher load capacity overall. I think it's a valid argument to caution against running a LT metric tire at air pressures around 35 PSI as a matter of course. The Nitto Tire documentation showing the heating of a LT tire at those pressures is pretty convincing as is the load capacity figure of 1500 lbs @ 35 PSI being inadequate for the GAWR of the vehicle (let alone offering any margin for safety).



I agree - the P-metric appears to be adequate for this application (hence they are OEM) and that's why I suggested that I was leaning towards one of them vs. the LT-metric - even though the LT was the correct/OEM size. I would prefer to avoid LT-metric tires if possible for their drawbacks that I mention in my earlier post (higher required tire pressure being just one).

What was the dealers objection?

Sorry my mistake. That should be 906 kg. Stupid Imperial system

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Tarkus is So Lost#000345
KJ Expeditionary Group
31" MT/R's and Rustys lift

T^2
I think that you are missing the point
put a side the P metric and LT and simply look at the tire as holding weight I can promis you that you will never over load a C range tire on a KJ to the point that it will damage it you will sit on the bumpstops first
a tire made to run 33 psi at ~1900# will still need to run at ~30 psi to get even wear but will ride like a tire that is holding 1900#
on the other hand a tire made to hold ~1900# at 50 psi will wear good and ride better at ~30psi and if you know that you will be holding a load you can put air in and it will hold a bead better at 16 psi on the trail

also you posted that you could get 1575# per tire in a worst case situation
trust me ,I know weight, you will NEVER load a KJ to 6300# and drive it for a log distance

and where did you find a C range tire that will fit a 16" rim but will only hold 1500#?

ok the post was questioning Revo's so I took a look and this is what I found

225/75D 16 2335 @ 65psi run this tire st 65 psi and you just as well be riding on a psc of farm equipment but it would be fine and no heat problem at ~1000# and ~30 psi

235/70 16 1984 @ 44 psi this one will not be as bad at max psi but would ride just fin and like above at ~1000# and ~30psi would have no heat problem
I woud bet that if you realy look at it some where around 34 psi would be perfect and thats only 10psi under max but i would not go under 18psi on the trail

245/70 16 2094 @ 44 psi same as above


you could run any one of these 3 on a stock rig and be fine you will never over load any of them and if you dont feel safe running it under max marked psi then you could do that but I would stay away from the 225/75

Just to throw my 2 cents in,"P" is more for passenger cars and"LT" is for light trucks.What do you consider your CRD to be a car or truck?The LT tires will have stiffer sidewalls and will handle better on road and under load than P tires.You don't have to run the high psi ratings,you can run your recommended psi for the CRD and will be fine.I run LT265/75R16 MT/R's on my KJ at 38 psi and get a great ride and wear(no flat spotting at all even when it sat for 6 months in storage) even when towing my trailer loaded at 4000 lbs.These are load rande "D" tires with a 10 ply rating.The 245/70 revo's are probally your best bet for a good AT tire for occasional towing and fishing trips,they will handle better in the rain/snow to.Just my 2 cents though.

like i put in another post, i ran E rated 245/75 16s dunlop radial rover R/T for over 45000 miles. no problems with flat spotting even when using them daily at 20-25 psi in the winter down to 0 degrees.

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The CRD has a front GAWR of 2750 lbs (if memory serves). Add the front and rear GAWR and that gets you to 5900 lbs max. Is it possible to get to the 3150 lbs GAWR on the rear? Assume again for argument sake that the 4300 curb weight is distributed evenly - that would leave 1000 lbs (+/- a few hundred) for cargo and tongue weight. Is it possible to reach 1000 lbs (+/- a few hundred) towing a trailer and hauling gear? It doesn't seem like a stretch to me.

Agreed - even wear is an important issue. Achieving the correct tire profile (correct inflation vs. over-inflation vs. under-inflation) for the particular vehicle and operating condition is the goal. I suspect that the CRD would not have enough weight to give a LT-metric tire the correct profile if filled to 50 PSI (it would be rounded/over-inflated). To get the correct profile, I suspect that you would have to run it at considerably less pressure and at the same time a lower load capacity then if running a P-metric tire (< 35 PSI, < 1500 Lbs). On the other hand the CRD is heavy enough to produce the correct tire profile with a P-metric @ 30 to 33 PSI and the load capacity will be > 1800 to 1900 lbs.

I suppose one could play games and run an LT-metric tire at 33 PSI for normal unloaded driving (so that you can get the correct tire profile) and add pressure for when loaded - but why bother?

According to the Bridgestone material - A C range LT-Metric tire has a max load capacity of 1500 lbs at 35 PSI. The C range LT-metric has a maximum capacity of 1940 Lbs at 50 PSI (all assuming LT225/75R16 size).

Since I don't intended to use the vehicle for rock crawling/advanced trail work - how well it holds a bead while lowering pressure doesn't concern me much. One the other hand, I can see packing the thing full of gear and pulling a trailer in the future...

Agreed.... No suggestion here to run at such elevated pressures. Not only would it ride rough, the tire profile would be all wrong. The tire would be rounded and you'd only be using the center of the tread.



Again assuming even weight distribution - the curb weight of the vehicle would exceed a 1000 Lbs capacity, let alone leave a margin for safety.



Agreed - I wouldn't suggest such an excessive pressure for this P-metric tire either. Again you would have a rounded profile.



Agreed - I would say that the correct pressure (for this vehicle) to get the right profile on the P-metric would be somewhere in the neighborhood of 31 to 34 PSI. And as no surprise - that just happens to match factory spec.




Actually I would never feel safe running at the "max marked psi" – at least on this vehicle. Again the max will give you improper inflation profile - rounded and running only on the center tread.