Tires

[ClarkstonGT]

A few questions about tires. When I bought my wag a year ago it had some no-name all terrain tires. They are P235-75-15s. They are noisy and ride like crap. However, they were great the times I had them in the snow. Also they require 50 psi of pressure which seems unusual for a tire that size.

Anyway, I am looking at replacing them very soon. I am wondering what you guys would recommend. I mostly drive around town and only get on snow when skiing in North Carolina about 10 times a year (I doubt I'll ever get in the mud). I like the looks of the AT, but hate the noise. I want something that is quiet, has a nice ride, looks good, has whitewalls and is adequate on ice and snow. I appreciate the help.

[BIGYELLOW78J10]

Hey,

Are you sure they require 50psi? That sounds like the max psi to me. The pressure should set according the vehicle specs on the doorjamb or in the glove box.

The tire I would choose would be an issue of money. I have michelin LTX m/s on my toyota. The tread is not very aggressive, but very quiet. I've driven in ice and rain and some mud, and I didn't have trouble, but I also drove cautiously. I have yet to take the truck in bad mud, but with 30x10.5 tires, I doubt I will.

Most manufacturers make a H-something model which is a highway tire. My Michelins haveworn very well, but cheaper tires are out there. 42,000 miles on them and they still have 3/8" of tread. maybe you should buy the tires off my truck. Then I can put 33"s on my J-10. oh yeah. Sorry for the rambling, hope it helps.

Daniel

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78 J-10 Rumblin Wreck (http://www.prism.gatech.edu/~gte644i/TRUCK.jpg)
2v 360 V-8
Stock down to the rust
Highway speed in about an Hour

[newbie]

Yeah, 50 psi seems mighty high...I wouldn't reccomend any more than 32-34 psi for a street tire. I have BF Goodrich All Terrain KO's (31x10.50) on my daily driver (Ford Explorer) and after 20,000 miles I can honestly say that I'm very impressed. Although they lack grip in mud of any kind, they do just fine on dirt, sand, and driving around town. Living in Texas, we don't see much snow or ice, so I can't report on that, but if you are looking for a tire that rides well, wears well, and gives decent traction off-road, look no further than the BFG A/T.
Try and stay away from BF Goodrich's cheap off-brand tire (I think they are called USA-1's) They got don't handle heat very well and they wear out very fast! Hope this helps.

Good luck,
Gary (newbie)

BTW, they are pretty quiet at highway speeds as well.

[This message has been edited by newbie (edited April 25, 2001).]

[ClarkstonGT]

Nope. The tire says on the side wall - max load 900 kg at 50 psi (cold). The guy who did my last rotation and balance also pointed this out to me. Up to then I had only been running them at about 35 psi. He said they were supposed to be at 50. I suspect that's why they ride so crappy and the front end feels so squirrely. I can't wait to get rid of them. They are actually LT235-75-R15 M+S tires for what it's worth.

BTW Rumblin, I noticed you are in the ATL. From you sig, I would guess you are a Tech fan.

[SpruceMoose]

i'm running 30x9.5 bfg radial all terrains. the older type, not the new KOs. i've got about 46k miles on them now, they will go at least another 7500. they are rated at 40k mi. i've been running them at 40-45 psi since new, with rotation and balance every 3-5000 miles. they look great, and barely any noisier than the p235 hiway tires that were on the rig when i got it about 4 years ago. remember, the manufactures recommended tire pressure is for the oem-type hiway tires, not the at/mt types. also, they always sacrifice handling for "ride quality", hence fairly low recommended pressures. use what "feels" right, get advice from others using the same tire on the same type of rig, but NEVER exceed the tire mfgs rating!
have fun!

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88 Grand Wagoneer
"Spruce Moose"
http://www.FSJtheMoose.homestead.com/files/small_jeep_in_woods_1_cropped.gif
AMC 360, DANA 44 F/R 2.72, TF 727, NP 229
Jacobs Pro-Street Ignition, Edelbrock 4bbl Intake with Holley 2bbl Analog Pro-Jection
Flowmaster 2.5" 50 Series Delta muffler and tubing
Amzoil foam air filter, Amzoil fluids all around
30x9.5 BFG AT
HF,VHF,UHF ham rigs and too many antennas (not)
8-Ball shift knob from college (1975)
Hella aux. driving lights

Next: 3" Rough Country 4-spring lift, Killer32 Bumpers and nerfs, 31 or 32" A/Ts

Mileage? We don't need no stinkin' mileage!

[243]

Two other AT tires you might consider are the Cooper Discoverer LT

http://www.coopertire.com/tire_cooper/images/tires/discovererLT.jpg

and the Dunlop Radial Rover RV

http://www.dunloptire.com/products/imx/radial_rover_rv.gif

They are normally about 25.00 cheaper per tire than the BFG's. I run Bridgestone MT's on my Dodge and a buddy runs BFG AT's on his. Both tires hold up well under the weight of the diesel (app. 4300lbs on the front axle). I plan to switch to an AT when the next set are needed because I don't need the MT very often.

I can second the Michelin LTX, the Dodge boys are getting excellent mileage from them.

I am definitely going with one of the AT's on the Jeep.

243

[mnoeltne]

<BLOCKQUOTE>quote:</font><HR>Originally posted by ClarkstonGT:
Nope. The tire says on the side wall - max load 900 kg at 50 psi (cold). The guy who did my last rotation and balance also pointed this out to me. Up to then I had only been running them at about 35 psi. He said they were supposed to be at 50. I suspect that's why they ride so crappy and the front end feels so squirrely<HR></BLOCKQUOTE>

Max pressure on the sidewall doesn't have anything to do with what you should have the tire inflated to. That is just the maximum pressure that the tire should ever be inflated to, no matter what. Always follow the tire inflation guidelines in the owners manual for your vehicle. They are also usually on the door post or inside the glove box lid as someone above pointed out. The specs given in those places are for your vehicle. You can vary from those a bit when you are in other conditions, but you always want to start with the vehicle manufacturers inflaction recommendations.

Running at the tire's max inflation pressure will indeed make it ride rough, and drive squirley. It can make it especially dangerous in the rain or snow.

Mark N

[bigjeepguy]

The best technique to figure out proper air pressure imho is to make a line across the tire with chalk, and drive around the block a couple times and see if it wears evenly across the tread which is ideal pressure, or if it wears on the center lower pressure is needed, and the opposite is true if it wears on the edges.

------------------
Jonathan landon
1973 J-4000 3602v ,TH-400
Dana20,Dana 44's

[BIGYELLOW78J10]

Well, I do attend Tech. It's about to be finals week, so I can't really consider myself a fan. Ma Tech is no friend of mine. But where else is an engineer gonna go in GA?

I still say the rating on the tire is the maximum safe air pressure, not the actual proper tire pressure. I've had plenty of service station guys tell me my tires should be run at that pressure. But the engineers who designed the rig designed them to run on tires at a certain pressure. If you run your tires at 50, the pressure will be far above 50 when the tire is running. And your likelihood of a blowout is increased if you hit something with the tire. I run my tires at most 5 psi above the recomendation on the truck, not based on the max tire pressure.

Daniel


------------------
78 J-10 Rumblin Wreck (http://www.prism.gatech.edu/~gte644i/TRUCK.jpg)
2v 360 V-8
Stock down to the rust
Highway speed in about an Hour

[WINGO]

Bigjeepguy has it right. Follow his advise if you want maximum traction on the road and good tread life.



------------------
WINGO
Vineland, NJ
USA
http://albums.photopoint.com/j/Thumbnail?u=1330817&a=11068485&p=38536654&Width=100&Height=100&Sequence=0
1984 GW 360
Rough Country/Heckethorn 2 1/4" AAL (actual lift)
Rough Country/Heckethorn Nitro 9000 Shocks
Performance Accesories 3 " Body Lift
31" X 10.5" Kelly MT

Soon to Have:
1- Rhino Grill
2- Alis-Chalmers Orange & Black Durabark exterior paint.

[ClarkstonGT]

I hear what you are all saying. However, I have never seen a tire say anything about 50 psi before. Most radial tires I have seen say 35 psi. This includes the Dunlop Rovers I had on my Grand Cherokee. Also, the tire doesn't say that the max pressure is 50 psi, it says the max load is 900 kg (at 50 psi). Finally, my friend who owns Alpha Tire in Clarkston pointed out the 50 psi requirement. My wife has Bridgestone ATs on her Isuzu. I'm gonna see what they say when she gets home. I'm not trying to belabor this, I just want to know what the right answer is. Underinflation can lead to a blowout just like overinflation. Either way, I want the things out of here.

Daniel - I got out of Tech in '94 with an ME degree. You become a much bigger fan when you finally escape. I'm working on my MBA at GSU now.

[ClarkstonGT]

FYI, I just looked at the wife's truck. She has Bridgestone Duelers. They say 35 psi max at whatever the max load is (I didn't note that). I really think these tires are supposed to be inflated to 50 psi.

[newbie]

The best technique to figure out proper air pressure imho is to make a line across the tire with chalk, and drive around the block a couple times and see if it wears evenly across the tread which is ideal pressure, or if it wears on the center lower pressure is needed, and the opposite is true if it wears on the edges.
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Jonathan landon
1973 J-4000 3602v ,TH-400
Dana20,Dana 44's


-100% correct, no matter what the "max load" at "X" psi says.

[78Chief]

When doing the chalk thing, try to avoid taking turns too.

[243]

ClarkstonGT

It could be that the tire on your Jeep was really intended for another application and has a higher load range than needed. Some tire manufacturers have the same size tire in two load ranges.

Cooper Discoverer A/T's are offered in a 245/75/16 C and a 245/75/16 E.

On my Dodge, it came with 245/75/16 E Load Michelins, 85psi max. My first set of Dunlop Mud Rovers were 235/85/16 E Load, 85psi max.; and, my most recent set of Bridgestones in 285/75/16 D Load are 65psi max. Different load range, different maximum pressure.

243

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by ClarkstonGT:
I hear what you are all saying. However, I have never seen a tire say anything about 50 psi before. Most radial tires I have seen say 35 psi. This includes the Dunlop Rovers I had on my Grand Cherokee. Also, the tire doesn't say that the max pressure is 50 psi, it says the max load is 900 kg (at 50 psi). Finally, my friend who owns Alpha Tire in Clarkston pointed out the 50 psi requirement.<HR></BLOCKQUOTE>

You only inflate the tires to the maximum pressure if you are running maximum load. So unless you have an 8000lb FSJ, you don't need to run them at maximum pressure, since you're not approaching the maximum load for those tires.

Most passenger-car radial tires have a 35psi maximum, because they have a lower load-rating; they are designated with a "P" in the tire-size (i.e. P235/75-15). True light-truck tires usually have a 50psi maximum, because they are designed to stand a higher load; they are designated with an "LT" in the tire-size (i.e. LT235/75-15).

I've had two 235/75-15 tires off of rims before, one a Passenger-rated tire, and one a light-truck rated tire, and believe me, just from the difference in weight you can tell you are dealing with two different animals. The sidewalls are much stiffer on the LT tires, and the carcass seems to be designed heavier overall.

So, you only use max-pressure if you are hauling max-load; if you are loading the tire less, you reduce the air-pressure.

It is kind of scary that a tire-shop OWNER doesn't know the difference between maximum pressure and recommended or normal operating pressure.

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Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/