What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Street Tire Pressure for Big Bias Ply Swampers?

dbreid

dbreid

1/2 ton status
Joined
Dec 26, 2005
Posts
380
Reaction score
0
Location
San Mateo CA
All,
Firstly, I know no one will have an "exact" answer (because there probably isn't one), but I am looking for advice. I have an 84 K30 on 17" tims, with 39.5" Bias Ply TSL's. I traditionally drive them around on the street (rarely, of course) with about 25psi in them. On the trail, I air down to about 10 or so (depends on the trail). Keep in mind, this is a pretty heavy truck in full battle dress. Twin fuel tanks, a full set of spares, tools, two people and camping gear. This is no Jeep... :)

I am wondering if higher PSI would be better on the street? I am not actually looking for handling, so much as preventing the tires from overheating due to sidewall flax on long drives. I am headed about 5 hours away (driving, not trailering) and I want to make sure I treat the tires as well as I can on the street.

Thanks in advance!

Dan
 
I ran 38" TSLs on my crew cab with 16.5s and only ran about 20-25 psi and the held up rather well considering this was in El Paso and it was my DD. I did get flat spots that took 2 miles or more to warm up. I don't think with a tsl you will have to wory that much about the sidewall flex heat issue due to the stifness and strength of the sidewall. I couldn't see a bulge in mine until I got below 10 PSI.

What is the max psi they call for and what is the max weight at that psi? If you think you are anywhere near the max weight for the tires go ahead and air them up or if not, just find what you think is a comfortable medium and go with it.
 
Here's a link that might work.

http://coloradok5.com/forums/search.php?searchid=859732


I went back and added some "Tags" to a few relevant posts on tire pressure. If you do a "Search" (upper right corner) and Select "Advanced" you can search for specific tags in a thread.

I've added:

bias ply pressure
correct PSI
PSI
tire pressure


to a few threads that had good information in them. Hopefully this will make life easier for other folks later on who want to find this same info.


:usaflag:
 
mudboggink5 said:
I run about 40 psi in my 38" swampers, works good on the street for me.
Click to expand...

40 PSI in a bias-ply Swamper??? :yikes:

I run 18 PSI, and that's about perfect. I'd guess you're going to completely burn through the center 4" of your tread....


:usaflag:
 
Wow dude, check the sidewall because my swapers say max cold pressure 30 psi.

For the search impaired (or the results could just be too old now)

Grim Reaper wrote up an awesome tire pressure thread a long time ago. The short version is it takes some trial and error to get the pressure right for your vehicle. If you drive for 10 minutes at freeway speeds and the tire pressure increased by more than 10% you're running not enough air. If it increased less than 10% you're not running enough air. Gotta make sure you're starting with cold tire pressure though. I did all my checking at night. Check em as I left work, then pull over after getting off the freeway and check the hot pressure.

This got me running 22 psi up front and 20 psi rear with my K5. Tires wore pretty good, I have over 20,000 miles on them and they're almost down to the wear bars now. I put 2500 miles of highway driving on them going to and from Blazer Bash (Average 65-70 mph)

Rene
 
I'm running 20 PSI on the street right now. It sounds like I am in the ballpark. That test sounds like a good idea and makes sense.

If hot pressure is more than 10% over cold pressure, the tire is heating up too much and you need more air.
 
tRustyK5 said:
If you drive for 10 minutes at freeway speeds and the tire pressure increased by more than 10% you're running not enough air. If it increased less than 10% you're not running enough air.
Click to expand...

One of these doesn't make sense... I assume you meant:

If you drive for 10 minutes at freeway speeds and the tire pressure increased by more than 10% you're running not enough air. If it increased less than 10% you're running too much air.

Is that right? Or am I missing something?
 
That was my guess. Either that or less than 10% is OK, in other words start low and keep adding a little air at a time 'till your pressure goes up less than 10% hot.
 
dbreid said:
One of these doesn't make sense... I assume you meant:

If you drive for 10 minutes at freeway speeds and the tire pressure increased by more than 10% you're running not enough air. If it increased less than 10% you're running too much air.

Is that right? Or am I missing something?
Click to expand...

Sorry guys, still getting used to working night shift again. :doah: It should have read; if the pressure goes up more than 10% your pressure is too low. If it goes up less than 10% your pressure is too high. 10% increase over cold pressure is the goal for warm tires and should be ideal for your particular truck.

Rene
 
I've got a K20 running on 36x13.50/17 Bias IROKs, and I've had really good wear with 25 front and 20 rear. Sounds like yours will be a little heavier with dual tanks and extra gear, so I would think 25-28 all around would be good.:D
 
sub on 17" rims 42 iroks and i run 20 to 22 i might try a little lower but so far seems good. Preaty much full dress also with a bigblock
 
Greg72 said:
40 PSI in a bias-ply Swamper??? :yikes:

I run 18 PSI, and that's about perfect. I'd guess you're going to completely burn through the center 4" of your tread....


:usaflag:
Click to expand...

I guess i should double check the tire pressure, and maybe lower it alittle.
 
You must log in or register to reply here.

Latest Posts

Top Bottom