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BriEOD
06-06-2005, 08:26 PM
Ok, I remember a big disscusion on the "old" board about this. Fitz had a tire blow and then there was a big debate. Anyhow, to the present what psi is everyone running their trailer tires at?

MarkP
06-06-2005, 08:31 PM
You know I don’t remember. I do run them within a couple of lbs of the max. Just lower. This year I am going to have Costco fill them with whatever gas they use now. Supposed to eliminate expanding as they heat.

Cary K.
06-06-2005, 08:31 PM
I was told to run them at the listed pressure on the sidewall. I think mine are 50psi.

BriEOD
06-06-2005, 08:34 PM
I tried to get on the "old" site but the URL didn't load. I seem to remember the debate was either run them at max 50psi or at 35psi. I also seem to remember RickD had a lot to say on the subject.

BriEOD
06-06-2005, 08:35 PM
The problem I would think with 50 psi is as they rotate they will heat and cause the pressure to rise over the max psi (theoretically in my head anyway).

Cary, you're on lake Gaston right?

Leroy
06-06-2005, 08:37 PM
Mine are at 50PSI.

BriEOD
06-06-2005, 08:39 PM
Leroy, can you offer any explanation as to why you run that at 50?

Leroy
06-06-2005, 08:41 PM
It's marked that way on on the sidewall.

SkySkiSpokane
06-06-2005, 08:41 PM
My tires say "max pressure cold"
I have always assumed that this meant they took account for road and outside air temp heat expansion. :confused:

Leroy
06-06-2005, 08:44 PM
I'm surprised most of the new tires for cars seem to be at 44PSI.

MarkP
06-06-2005, 08:45 PM
The problem I would think with 50 psi is as they rotate they will heat and cause the pressure to rise over the max psi (theoretically in my head anyway).

Cary, you're on lake Gaston right?
Brian,

Don’t you get tires at the Costco. The last time I got my truck tires rotated at CostCo they put green caps on the stem. When I asked, “what’s up with that”, he told me they started using nitrogen (I think he said Nitrogen) to fill the tires now because it doesn’t expand and contract..

Anyone else see that at Costco??

BriEOD
06-06-2005, 08:46 PM
It's marked that way on on the sidewall.

It's marked as MAX pressure right? My point is if you check your automobile driver side door jam it will give you the recommended tire size and pressures. My truck tires have a max pressure of 50 psi but the vehicle manufaturer recommends running at a lesser pressure. So, I've got my tires on the boat trailer at 40 psi. But, I'm going on vacation in a few weeks and gonna be towing for 5-6 hours and don't want to have a blow out. So, what's the consensus here?

BriEOD
06-06-2005, 08:47 PM
Brian,

Don’t you get tires at the Costco. The last time I got my truck tires rotated at CostCo they put green caps on the stem. When I asked, “what’s up with that”, he told me they started using nitrogen (I think he said Nitrogen) to fill the tires now because it doesn’t expand and contract..

Anyone else see that at Costco??



Dude I'm not sure we even have a Costco down here?? If we do I don't know where it is. I got my Marathons on TireRack.com.

Cary K.
06-06-2005, 08:49 PM
Cary, you're on lake Gaston right?

No, but not too far from there, maybe 45 min. I'm in the Wilson/Rocky Mt area on I-95 (Tar River Reservoir). I go to Gaston 5-6 times a year though.

MarkP
06-06-2005, 08:52 PM
I got my trailer tires at the Goodyear shop. But when I talked to the Costco guy about doing my trailer tires he said they are not supposed to but bring it by and he would fix me up.. I wanted to have it done for all of the highway driving this year.. (Norris, Gaston)

Cary K.
06-06-2005, 08:53 PM
Quote from MYMC on the MYMC site:

Yes, that is what MasterCraft is telling me. 50PSI is the correct inflation pressure for all trailers.

Here is the link for anyone that wants to verify:

MC Trailer Tire Pressure (http://mymastercraft.com/Forum/view_thread.cfm?postid=224&forum=224&category=2)

Ben
06-07-2005, 07:20 AM
I'm in the 50 PSI COLD group. Also assuming Goodyear did the math, since they wrote COLD on my tires... Towed 9 hrs each way one time like this last summer w/o issues.

Too low of a pressure WILL cause the tire to heat up, since you are working the rubber sidewalls more. It will also make the ride smoother, which is probably why the auto companies may run a bit lower than sidewall pressure.

87Craft
06-07-2005, 07:44 AM
If I'm not mistaken, it tells you the recommended psi on a COLD and UNLOADED tire.

BrianM
06-07-2005, 09:57 AM
I'm in the 50 PSI COLD group. Too low of a pressure WILL cause the tire to heat up, since you are working the rubber sidewalls more. It will also make the ride smoother, which is probably why the auto companies may run a bit lower than sidewall pressure.

I do the same thing and was told running lower pressure would cause just what you said. My tires state 50psi COLD on the sidewalls. Also max PSI COLD is where the highest load limit will be achieved.


My truck tires have a max pressure of 50 psi but the vehicle manufaturer recommends running at a lesser pressure.


Vehicle manufactures have different reccomendations based on suspension, steerting, handling etc. characteristics that they feel work best with each particular model. I run my vehicle tires by what it says on the door.

Leroy
06-07-2005, 10:17 AM
BriEOD; I think more tires blow from bearing heat than tire heat, just my theory, feel each hub on a test run and as you drive, it's pretty obvious which one is hot! I would go with 50 PSI cold pressure, but must be the rating on the tire, I think the difference in pressure between loaded and unloaded is negligible (you could test by putting gauge on tire and jacking up that wheel to see if there is any difference), and Cary confirmed through MYMC that 50 PSI is correct for all MC trailers.

Small things, make sure you have an empty tank when you tow and don't use the boat as a trailer to carry stuff!

Informative thread!

Leroy
06-07-2005, 10:18 AM
Also, check the load rating vs the weight on each tire.

east tx skier
06-07-2005, 10:27 AM
I'm a little late to chime in, but running 50 psi because (a) that's what the tires say, and (b) that was the consensus I drew from the previous discussion to which Brian made reference.

Thrall
06-07-2005, 11:38 AM
BriEOD,
Run them at 50psi (as long as they're rated for that). If I remember correctly you have a singleaxle trlr. Thats alot of weight for 2 tires. Run at the max allowable cold pressure.
The tires will build less heat the harder they are (more psi = less rolling resistance).

G-man
06-07-2005, 11:49 AM
Thrall is correct. If you look at the weight rating for the tire it will say X-lbs at max pressure cold. I also ran my single axle trailer at 50 psi.

east tx skier
06-07-2005, 11:56 AM
The max on Marathons for 215/75/14 is "C" rated if memory serves (about 1,760 pounds per tire).

BriEOD
06-07-2005, 02:02 PM
Everyone thanks for the replies.

jayocheskey
06-07-2005, 03:07 PM
Nobody knows more about tires than the people who manufacture them. On every tire, there is a recommended PSI -- ALWAYS follow this. If you over-inflate or under-inflate, you are asking for trouble whether it's a blow-out or loss of control. It's as easy as seeing the a number on the sidewall and inflating (or in some cases, deflating) your tire to that PSI.

I worked at a tire store a few years in college.

BRAZOS 205
06-07-2005, 03:08 PM
Just make sure you have an aired up spare tire and jack that will fit your trailer for your trip.

I believe the marathons are 1860 lbs @ 50 PSI cold, which is funny because that is 3720 lbs carrying capacity on single axle trailer. P205 is 2800 lbs + 800 lbs of trailer = 3600 lbs. That leaves 120 lbs for a tower, tower accessories, fuel, skis, boards, etc.
Not much wiggle room.

I run at 50 PSI.

lakes Rick
06-07-2005, 05:57 PM
My comments, from another thread, were fresh in my geezer brain as I had just read an article about trailer tires... What I remember

1. Too low of pressure causes heat which causes tires to blow

2. Trailer tires are different than car tires.. A stiffer sidewall to hold up the weight on a "trailer".. MOST trailer tires wear out in the sidewalls, NOT the tread.. This is why you need to check your trailer tires all over, not just the tread.. The sidewalls get old and soft then wear out usually leading to a blow out..

3. CRITICAL to keep your TRAILER tires at maximum cold pressure.. The article said this is what gives your TRAILER tire its strength and load capacity....

4. My tires have a cold max pressure of 55pds....

5. The article recommended to run LESS pressure ( around 30 pds) when storing for the winter.. It will give you longer tire life, or technically longer SIDEWALL life, which is what a TRAILER tire is all about..

6. Obviously a tandem trailer distributes its load more evenly than a single axle..

7. Article recommended AGAINST using auto tires on a trailer..

8. Some trailer tires have better load ratings than others.. READ the specs..

9. As to why most of you are bald and have a small peenis is beyond my realm of knowledge........ Rick

BriEOD
06-07-2005, 07:47 PM
9. As to why most of you are bald and have a small peenis is beyond my realm of knowledge........ Rick

LOL!! :purplaugh 50 psi it is.

east tx skier
06-07-2005, 10:38 PM
5. The article recommended to run LESS pressure ( around 30 pds) when storing for the winter.. It will give you longer tire life, or technically longer SIDEWALL life, which is what a TRAILER tire is all about..


Now I'm confused again. I put that in my winterization check list and someone else read it and said the exact opposite was the case, i.e., full pressure or slightly higher than full pressure.

Me so confused. :confused:

lakes Rick
06-07-2005, 11:25 PM
Now I'm confused again. I put that in my winterization check list and someone else read it and said the exact opposite was the case, i.e., full pressure or slightly higher than full pressure.

Me so confused. :confused:

Eastie, I can't remember where I read the article but is was very well done and I remember this point vividly...

But the one thing I remember from college ( all two terms of it) was that ONE person wrote that book we are being tested on .... Rick

east tx skier
06-08-2005, 10:03 AM
The point in lessening the pressure was to relieve pressure on the sidewalls, correct?

Leroy
06-08-2005, 10:15 AM
I remember the single axles not having much margin also.

I'm guessing lowering the pressure helps, but probably small help. The sidwalls are also extra strong on these tires. My racing bicycle with 170 psi tires said the same thing if you were going to store for awhile.


I believe the marathons are 1860 lbs @ 50 PSI cold, which is funny because that is 3720 lbs carrying capacity on single axle trailer. P205 is 2800 lbs + 800 lbs of trailer = 3600 lbs. That leaves 120 lbs for a tower, tower accessories, fuel, skis, boards, etc.
Not much wiggle room.

captkidd
06-09-2005, 10:05 AM
Brian,

Don’t you get tires at the Costco. The last time I got my truck tires rotated at CostCo they put green caps on the stem. When I asked, “what’s up with that”, he told me they started using nitrogen (I think he said Nitrogen) to fill the tires now because it doesn’t expand and contract..

Anyone else see that at Costco??



If my memory serves me correcty, the normal air we breathe is 78% nitrogen, 20+% oxygen, and the rest is other stuff (of course this is pure air, not the smoggy stuff we have in some places). Can't see how pure nitrogen would be much better, but I guess it couldn't hurt.

I'm with the 50psi group. I run at least 40psi in my vehicle tires (even though they say 35psi) because my tire guy says that they last longer and get better gas mileage this way. In the past, practically all my tires wore out on the edges of the tread instead of the middle (I like to go around curves too fast), and this seems to have helped a lot. It seems to me that underinflated tires are a much bigger problem; if you look at cars on the highway, you can tell that many of them have tires that are underinflated.

h20_skidog
06-09-2005, 12:32 PM
I checked my trailer tires last night and I have the Goodyear Marathon 225/75R15 having a load range of "D" (max load of 2450 lbs @ 65 PSI cold).

Based on what I have read here:

Run at the max allowable cold pressure!
On every tire, there is a recommended PSI -- ALWAYS follow this!
CRITICAL to keep your TRAILER tires at maximum cold pressure!
But then MYMC confirmed that 50 PSI is correct for all MC trailers??? :confused:

Unless somebody can convince me otherwise, I believe I'm going to keep my tires at 65 PSI and 35 PSI during the winter layup.

east tx skier
06-09-2005, 03:06 PM
Are you running the D-rated tires? That would explain the greater load range, etc. Can't go higher than C-rated on a 14" rim. Yours are 15" rims, right?

MarkP
06-09-2005, 03:35 PM
Ok

Just got home from having the air in my trailer tires replaced with Nitrogen. Ready for the road trips this summer now..:steering:

east tx skier
06-09-2005, 03:55 PM
Enjoy your Guiness tires.

Actually, come to think of it. I've got a bit of Nitrogen in my tires, too. :)

MarkP
06-09-2005, 04:07 PM
Enjoy your Guiness tires.

Actually, come to think of it. I've got a bit of Nitrogen in my tires, too. :)Thanks Doug,

I think I will and Y, yes you do.. The guy at the shop said it would eliminate expanding and contracting. He did it for nothing and wouldn’t even take a tip..

east tx skier
06-09-2005, 05:40 PM
Works for me. Where'd you have it done? Costco?

h20_skidog
06-09-2005, 09:23 PM
Are you running the D-rated tires? That would explain the greater load range, etc. Can't go higher than C-rated on a 14" rim. Yours are 15" rims, right?
Yes, the rims are 15" and the tires are D-rated.

MarkP
06-09-2005, 09:33 PM
Works for me. Where'd you have it done? Costco?
Yes it was at CostCo. They put the last set of tires on my truck and the last two on the Explorer. They didn’t sell the tires that I wanted for the trailer but he fixed me up with the nitrogen anyway.. I don’t know if it helps or not but couldn’t argue with the price..

KHall
05-23-2006, 08:34 PM
Should run trailer tires at rated max cold pressure. Any less w/ full load (hardly any margin on load w/MC trailers) causes additional tire sidewall flex which leads to overheating on long trips. This is especially true at high speeds.

Nitrogen is dry compared to air, but will expand w/ heating like air which is mostly nitrogen anyway.

1984StarsandStripes
05-25-2006, 08:22 AM
We race Late models here in the Midwest and the reason for the nitrogen is that it is dry "air". What is really expanding from the heat is the moisture inside the tire. so when we set PSI on a tire it stays within one psi of where we set it. Therefore, I would imagine on a trailer tire your max pressure is set cold this is also where the tire can carry the most weight so if the tire stays closer to this pressure it will carry mmuch closer to its recommend weight rating.

Just my :twocents: worth!