New PUP tires

[Travisma 1,317]

Getting the PUP ready for our month end trip.

 

Bought it used last year, it's an 85 Coleman.  Total weight with hitch and stored items is a GVWR 1330 lbs. and  GAWR axle rating of 1180..

 

Previous user had said the tires were about 2 years old when we bought it..  They look good, still have the little nubs sticking out.  But when I looked for the manufacturing date, it looked like it was 2010.

 

So I figure it's time for new ones.

 

They are small, 4.80 x 8 and they say 2 ply.

 

I can get replacement tire/wheel combo at a Harbor Freight up the street for around $30.

 

They say road, high speed 4 ply, rating B but the max weight is 580 pounds.

 

Wal-Mart carries a similar deal, but a 6 ply, load rating of C.  No specs for the max weight.

 

So here's the dumb question, is the weight of the PUP divided evenly onto the 2 tires, so I should be looking at a max weight per tire of about 650 or do I use the axle of 590?

 

Since it currently has a 2 ply tire, will the 4 be ok even if the max weight is a little low or should I just go with the 6 ply w/o a listed weight spec. ?

 

Any downside of extra plys?  Too stiff/bouncy ride?

 

And yes I'm going to clean and repack the bearings while I have the wheels off.

[arthuruscg 34]

Forget about the nubmer of plys and go by the rating.

 

What does the trail plackard say is the load and tire size requirement?

 

I would think Load rating C would be approprate with 4.8*8 tires. How much space do you have between the tire and the wheel wells? If you are looking to raise the camper, 4.8*12 LR B would raise the camper 2".

 

http://www.etrailer.com/faq-trailer-tire-sizing-tables.aspx

[Travisma 1,317]

Forget about the nubmer of plys and go by the rating.

 

What does the trail plackard say is the load and tire size requirement?

 

I would think Load rating C would be approprate with 4.8*8 tires. How much space do you have between the tire and the wheel wells? If you are looking to raise the camper, 4.8*12 LR B would raise the camper 2".

 

http://www.etrailer.com/faq-trailer-tire-sizing-tables.aspx

Don't think they would clear, plus don't really need to raise it.

 

Owners manual says 4.8x8 at 60 psi.  No ply rating.  They also did say that you should follow the tire mfg. suggestions.  Who knows what was on there originally.

 

When I was looking at the 4 plys on line I didn't think their weight rating was high enough, that's why I'm leaning towards the 6.  I was shocked last night when I looked at the current ones and they were only 2 ply.

 

That's a pretty interesting link.

[parrothead7368 aka Norm 101]

4.8X80 at 60 PSi would be a load range B.

http://www.etrailer.com/Tires-and-Wheels/Redline/480TW5-B.html

 

Best Regards,

Norm

[Travisma 1,317]

4.8X80 at 60 PSi would be a load range B.

http://www.etrailer.com/Tires-and-Wheels/Redline/480TW5-B.html

 

Best Regards,

Norm

See any problems if I go up to a 6 ply?

 

They are the same price as the 4s

[parrothead7368 aka Norm 101]

I don't think you would have a problem, but the PSI would change. There should be somewhere on the tire that has max pressure cold. Looks like load range C would me 90#.  If you don't do proper pressure it could be underinflated and have problems with the tire.

 

Best Regards,

Norm

[Travisma 1,317]

I don't think you would have a problem, but the PSI would change. There should be somewhere on the tire that has max pressure cold. Looks like load range C would me 90#.  If you don't do proper pressure it could be underinflated and have problems with the tire.

 

Best Regards,

Norm

I saw that. 

 

I was just wondering if the extra pressure/harder tire would make for a too rough ride for a 30 year old PUP.

[arthuruscg 34]

Completly ignore the number of plys, it does not translate into load ratings. The higher weight raiting should make very little difference in trailer bounce, but will give you extra safety margin.

 

The down side of 4.80 x 8 LR C is having to pump the tires up to 90psi. Most gas station and cheep 12v pumps stop at about 60 psi.

 

If you can fit 5.7x8 LR B (715 lbs at 50 psi) then you will have almost the 4.80 x 8 LR C weight raiting at a much lower PSI.

[PGHFiend 140]

To add a little more info here, tire ratings at a certain psi are a linear conversion. If you could hold say 1000 pounds at 100 psi, you could calculate that you could hold 100 pounds at 10 psi. A lot of guys do this on thier tow rigs tires, to adequately hold the weight, without making too stiff of a ride and possibly wearing out the center of the tire. I run 60 pounds of air in an 80 psi max load range E tire on my diesel Ram. Checked with a heat gun often, they show even wear and run pretty cool at highway speeds.

[Travisma 1,317]

I went with the 6 plys. Hopefully I'll be able to find somewhere that can pump up,to 90 pounds and a gauge that can read that high.

[arthuruscg 34]

To add a little more info here, tire ratings at a certain psi are a linear conversion. If you could hold say 1000 pounds at 100 psi, you could calculate that you could hold 100 pounds at 10 psi. A lot of guys do this on thier tow rigs tires, to adequately hold the weight, without making too stiff of a ride and possibly wearing out the center of the tire. I run 60 pounds of air in an 80 psi max load range E tire on my diesel Ram. Checked with a heat gun often, they show even wear and run pretty cool at highway speeds.

You can do that with LT tires, but NEVER run less then the sidewall pressrue on ST tires.

[arthuruscg 34]

The MV50 handeled pumping up to 80 psi on my old tires just fine and VERY quickly compared to the cheep 12v pumps. One time I accidently let it pump to long and it went up to 100psi. To pump up from about 40psi, you will need to start the pump and then connect the hose (quick connect) other wise the start up draw will pop the 20 amp fuse.

http://www.amazon.com/gp/product/B000BM8RT8/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

The Accutire gauge is cheep, relable, and has is with in 1PSI of the expensive gauges solf by the Snapon and MACO tools guys.

http://www.amazon.com/gp/product/B00080QHMM/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

If you have not added any 12v outlets to your popup, the Blue sea ones are nice.

http://www.amazon.com/gp/product/B001U4ZZPK/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

[Travisma 1,317]

The MV50 handeled pumping up to 80 psi on my old tires just fine and VERY quickly compared to the cheep 12v pumps. One time I accidently let it pump to long and it went up to 100psi. To pump up from about 40psi, you will need to start the pump and then connect the hose (quick connect) other wise the start up draw will pop the 20 amp fuse.

http://www.amazon.com/gp/product/B000BM8RT8/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

The Accutire gauge is cheep, relable, and has is with in 1PSI of the expensive gauges solf by the Snapon and MACO tools guys.

http://www.amazon.com/gp/product/B00080QHMM/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

If you have not added any 12v outlets to your popup, the Blue sea ones are nice.

http://www.amazon.com/gp/product/B001U4ZZPK/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

thanks for the info