Want to upgrade tires

Cummins12V98 wrote:

taken wrote:

RoyF wrote:
What pressure do you actually need in a G-rated tire? I'm asking because I put one Sailun G-rated tire on my Hitchhiker-II after a blowout in May. I'm running 80 psi in the Sailun, same as the other tires: two F-rated, and one E-rated which hasn't blown out (yet).

You need to run max pressure to get max capacity. For example, here is Goodyear's inflation table for their RV tires. Scroll down to the second chart and you'll see the 614 specs.

Clicky

Inflation table for GY G

Weight/inflation
3170----85
3300----90
3415----95
3550----100
3675----105
3750----110

Changing from E to G tires most will need to use the top number and inflation. NOT MAX PSI!!!!!!

What in the world are you talking about with all your exclamation points? I said to get the max capacity you need the max psi. In other words, different pressures get you different capacities. I never said that everyone needed that. Calm yourself and take a deep breath. It's going to be ok.

2-MTnesters wrote:

Cummins12V98 wrote:


I think you should contact GY Tech Support.

I did when changing from GY E to GY G on our Avion Platinum. There is a weight/inflation chart for each tire.

Per GY they said to weigh the axles to determine tire load then use the chart add 5psi to that number. Tires have a "MAX" load psi that does not mean you have to run them at that psi. Mose RV's come maxed out weight wise based on what the tires can carry that is why the RV mfg says to inflate to XX and that usually happens to be the tires MAX pressure!

GY Tech said not to run 110 when only 80-85 is needed. Max psi 110 will make the RV ride much harder, wear the center of the tire and have less stopping traction then using 80-85 if that is what the chart says.

I ran 85 psi on the G's on the Avion for 5 years with even tread wear and never a problem.

I am doing the same going from GY G to H using the weight/inflation guide.

I was told that with my 7000# axels and GVWR of 5er being close to 16000# to run them at max pressure +- a few lbs. This came from the GY rep. I have always run my RV tires at max pressure at the recommendation of the tire reps and have never had any issues with wear or anything else. Maybe each circumstance is different but I will continue to do what is recommended by my selling dealer for my rig. I will say that IMHO Keystone has inferior tires on their Montana's by having the GY Marabombs installed. Tim

I've NEVER been told or read to add "a few extra lbs. psi" after airing to 110 psi...ONLY thing I've seen is if you are going to let the 5er set for months on end and tires are going to support the 5er, add 5 psi....Nowhere have I seen where it states to check tires, cold air pressure, air to recommended psi....and then, for good measure, add a couple more lbs..doesn't make sense.....If states to air to 80, air to 80, if 110, 110, if 65 then 65....having worked in and around tire manufacturing long enough to learn from the design and manufacturing engineers, that doesn't make sense to add " a few extra lbs" on top of the recommended air pressure for a particular tire.

Cummins12V98 wrote:

2-MTnesters wrote:

Me Again wrote:
A 2010 my require a wheel upgrade to go to G rated tires. So decide if you want to go to 17.5 rims or stay with 16". I would go Sailun S637 and rims if you need them, however make sure the larger diameter tires fit or you will have to pay for GY G614's. If that is the case I would go the 17.5 rims and 215/75R17.5's. The 17.5's are slightly smaller in diameter verses your Maratbombs.

Note a LT235/85R16G at 80 lbs inflation is rated at 3042(aka LRE).

Chris

OP shouldn't need a wheel upgrade as he has the same rig as me. Many Montana owners have done this very same upgrade and are able to use their factory rims with no ill effects. There is plenty of room between the tires and inside of the wheel well for the tire upgrade. As mentioned in my prior post, if you are not sure of the psi rating of your factory rims simply look on the back side of the wheel on one of the spokes. The pressure rating will be cast into the wheel. Also not sure why one would run their 'G' rated tire underinflated at 80psi when pressure requirement for that tire is 120psi. The more underinflated you run the tires the more heat that builds up which is the cause of MANY tire failures. 'E' rated GY Marathons required 80psi, I ran them at 80psi, 'G' rated GY G614's require 120psi, run them at 120psi. You can run them a few lbs under max but NOT 20-40# under. Tim

I think you should contact GY Tech Support.

I did when changing from GY E to GY G on our Avion Platinum. There is a weight/inflation chart for each tire.

Per GY they said to weigh the axles to determine tire load then use the chart add 5psi to that number. Tires have a "MAX" load psi that does not mean you have to run them at that psi. Mose RV's come maxed out weight wise based on what the tires can carry that is why the RV mfg says to inflate to XX and that usually happens to be the tires MAX pressure!

GY Tech said not to run 110 when only 80-85 is needed. Max psi 110 will make the RV ride much harder, wear the center of the tire and have less stopping traction then using 80-85 if that is what the chart says.

I ran 85 psi on the G's on the Avion for 5 years with even tread wear and never a problem.

I am doing the same going from GY G to H using the weight/inflation guide.

Just the opposite of what I was told by a GY Engineer when one visited one of our General Tire plants, which my company owns, (ie, General & Continental's)....Seeing as how I was a long time camper and had GY tires on my 5er, the GY G614s....I was told to run at max sidewall pressure of 110psi, same as Monaco recommended, (one's who built the Holiday Rambler 5er's. ).

GY G614's, have a max sidewall psi rating of 110 psi.

I've never noticed my 5er riding "hard or rough"...5er does have Monroe severe duty shocks on it, but I was told by Goodyear Engineer that running at max psi would keep heat down and I would get best wear out of the tires....Now we were talking about these tires being mounted on a 5er that has a GVW of almost 17,000#, but the reason given, though General, Continental, Michelin, and Goodyear ALL have "inflation tables", as well as a host of others....when it comes to towing, it was a general consensus that running tires at max sidewall pressure wouldn't hurt anything....guess there is a possibility of ride being rough, but last 2 5er's I've owned came with shocks and equal-flex suspension so maybe that's why I've never experienced a "rough' or "hard" riding towing experience.


It was also deemed by the design Engineers that 90% of the time, if not more...it's not "practical" to take weight of each tire to see exactly what psi to put in each time, or weight of individual axles...I neither have the time nor the resources to do this as often as it might need to be done...thus, running trailer tires at max sidewall recommended psi, (IF OEM was/is the same weight rated tire), is perfectly fine..nothing will happen...As you've stated, you've never had a problem with GY G614's, neither have I and I run them at what is recommended by GY as well as my 5er's manufacturer, 110 psi....

ON EDIT: "IF" I were to go from a G to an H rated tire on my 5er, THEN I WOULD adjust weight, or if going from an "E" to a "G"...but I was talking about OEM G rated tires or OEM E rated tires, not going up a weight range...then, at that time, I would adjust psi on the higher range tire.

Cummins12V98 wrote:


I think you should contact GY Tech Support.

I did when changing from GY E to GY G on our Avion Platinum. There is a weight/inflation chart for each tire.

Per GY they said to weigh the axles to determine tire load then use the chart add 5psi to that number. Tires have a "MAX" load psi that does not mean you have to run them at that psi. Mose RV's come maxed out weight wise based on what the tires can carry that is why the RV mfg says to inflate to XX and that usually happens to be the tires MAX pressure!

GY Tech said not to run 110 when only 80-85 is needed. Max psi 110 will make the RV ride much harder, wear the center of the tire and have less stopping traction then using 80-85 if that is what the chart says.

I ran 85 psi on the G's on the Avion for 5 years with even tread wear and never a problem.

I am doing the same going from GY G to H using the weight/inflation guide.

I was told that with my 7000# axels and GVWR of 5er being close to 16000# to run them at max pressure +- a few lbs. This came from the GY rep. I have always run my RV tires at max pressure at the recommendation of the tire reps and have never had any issues with wear or anything else. Maybe each circumstance is different but I will continue to do what is recommended by my selling dealer for my rig. I will say that IMHO Keystone has inferior tires on their Montana's by having the GY Marabombs installed. Tim

taken wrote:

RoyF wrote:
What pressure do you actually need in a G-rated tire? I'm asking because I put one Sailun G-rated tire on my Hitchhiker-II after a blowout in May. I'm running 80 psi in the Sailun, same as the other tires: two F-rated, and one E-rated which hasn't blown out (yet).

You need to run max pressure to get max capacity. For example, here is Goodyear's inflation table for their RV tires. Scroll down to the second chart and you'll see the 614 specs.

Clicky

Inflation table for GY G

Weight/inflation
3170----85
3300----90
3415----95
3550----100
3675----105
3750----110

Changing from E to G tires most will need to use the top number and inflation. NOT MAX PSI!!!!!!

2-MTnesters wrote:

Me Again wrote:
A 2010 my require a wheel upgrade to go to G rated tires. So decide if you want to go to 17.5 rims or stay with 16". I would go Sailun S637 and rims if you need them, however make sure the larger diameter tires fit or you will have to pay for GY G614's. If that is the case I would go the 17.5 rims and 215/75R17.5's. The 17.5's are slightly smaller in diameter verses your Maratbombs.

Note a LT235/85R16G at 80 lbs inflation is rated at 3042(aka LRE).

Chris

OP shouldn't need a wheel upgrade as he has the same rig as me. Many Montana owners have done this very same upgrade and are able to use their factory rims with no ill effects. There is plenty of room between the tires and inside of the wheel well for the tire upgrade. As mentioned in my prior post, if you are not sure of the psi rating of your factory rims simply look on the back side of the wheel on one of the spokes. The pressure rating will be cast into the wheel. Also not sure why one would run their 'G' rated tire underinflated at 80psi when pressure requirement for that tire is 120psi. The more underinflated you run the tires the more heat that builds up which is the cause of MANY tire failures. 'E' rated GY Marathons required 80psi, I ran them at 80psi, 'G' rated GY G614's require 120psi, run them at 120psi. You can run them a few lbs under max but NOT 20-40# under. Tim

I think you should contact GY Tech Support.

I did when changing from GY E to GY G on our Avion Platinum. There is a weight/inflation chart for each tire.

Per GY they said to weigh the axles to determine tire load then use the chart add 5psi to that number. Tires have a "MAX" load psi that does not mean you have to run them at that psi. Mose RV's come maxed out weight wise based on what the tires can carry that is why the RV mfg says to inflate to XX and that usually happens to be the tires MAX pressure!

GY Tech said not to run 110 when only 80-85 is needed. Max psi 110 will make the RV ride much harder, wear the center of the tire and have less stopping traction then using 80-85 if that is what the chart says.

I ran 85 psi on the G's on the Avion for 5 years with even tread wear and never a problem.

I am doing the same going from GY G to H using the weight/inflation guide.

2-MTnesters wrote:

Me Again wrote:
A 2010 my require a wheel upgrade to go to G rated tires. So decide if you want to go to 17.5 rims or stay with 16". I would go Sailun S637 and rims if you need them, however make sure the larger diameter tires fit or you will have to pay for GY G614's. If that is the case I would go the 17.5 rims and 215/75R17.5's. The 17.5's are slightly smaller in diameter verses your Maratbombs.

Note a LT235/85R16G at 80 lbs inflation is rated at 3042(aka LRE).

Chris

OP shouldn't need a wheel upgrade as he has the same rig as me. Many Montana owners have done this very same upgrade and are able to use their factory rims with no ill effects. There is plenty of room between the tires and inside of the wheel well for the tire upgrade. As mentioned in my prior post, if you are not sure of the psi rating of your factory rims simply look on the back side of the wheel on one of the spokes. The pressure rating will be cast into the wheel. Also not sure why one would run their 'G' rated tire underinflated at 80psi when pressure requirement for that tire is 120psi. The more underinflated you run the tires the more heat that builds up which is the cause of MANY tire failures. 'E' rated GY Marathons required 80psi, I ran them at 80psi, 'G' rated GY G614's require 120psi, run them at 120psi. You can run them a few lbs under max but NOT 20-40# under. Tim

According to the inflation table, max psi for the 614 G tire is 110.
Have I been using wrong information?

Me Again wrote:
G614's require 110 lbs not 120. OP's right near the time they upgraded wheels, so he should check them. G614 is about the same size as the Maratbomb. Sailun is one inch larger.

Chris

I stand corrected, 110psi not 120psi, at any rate the tires should be inflated to max pressure for optimal performance and minimal heat generation. Also the Sailun's will fit on the Montana as well. Others on the Montana forum have upgraded to those tires as well while keeping their factory wheels. Tim

Me Again wrote:

2-MTnesters wrote:

Me Again wrote:
A 2010 my require a wheel upgrade to go to G rated tires. So decide if you want to go to 17.5 rims or stay with 16". I would go Sailun S637 and rims if you need them, however make sure the larger diameter tires fit or you will have to pay for GY G614's. If that is the case I would go the 17.5 rims and 215/75R17.5's. The 17.5's are slightly smaller in diameter verses your Maratbombs.

Note a LT235/85R16G at 80 lbs inflation is rated at 3042(aka LRE).

Chris

OP shouldn't need a wheel upgrade as he has the same rig as me. Many Montana owners have done this very same upgrade and are able to use their factory rims with no ill effects. There is plenty of room between the tires and inside of the wheel well for the tire upgrade. As mentioned in my prior post, if you are not sure of the psi rating of your factory rims simply look on the back side of the wheel on one of the spokes. The pressure rating will be cast into the wheel. Also not sure why one would run their 'G' rated tire underinflated at 80psi when pressure requirement for that tire is 120psi. The more underinflated you run the tires the more heat that builds up which is the cause of MANY tire failures. 'E' rated GY Marathons required 80psi, I ran them at 80psi, 'G' rated GY G614's require 120psi, run them at 120psi. You can run them a few lbs under max but NOT 20-40# under. Tim

G614's require 110 lbs not 120. OP's right near the time they upgraded wheels, so he should check them. G614 is about the same size as the Maratbomb. Sailun is one inch larger.

Chris

You beat me to it Chris...I was looking back while posting and read he had stated 120 psi for G614's...as you stated, not correct....max sidewall psi is 110lbs. That is what Goodyear, as well as placard on my 5er recommends to run in the GY G614's, 110psi..

2-MTnesters wrote:

Me Again wrote:
A 2010 my require a wheel upgrade to go to G rated tires. So decide if you want to go to 17.5 rims or stay with 16". I would go Sailun S637 and rims if you need them, however make sure the larger diameter tires fit or you will have to pay for GY G614's. If that is the case I would go the 17.5 rims and 215/75R17.5's. The 17.5's are slightly smaller in diameter verses your Maratbombs.

Note a LT235/85R16G at 80 lbs inflation is rated at 3042(aka LRE).

Chris

OP shouldn't need a wheel upgrade as he has the same rig as me. Many Montana owners have done this very same upgrade and are able to use their factory rims with no ill effects. There is plenty of room between the tires and inside of the wheel well for the tire upgrade. As mentioned in my prior post, if you are not sure of the psi rating of your factory rims simply look on the back side of the wheel on one of the spokes. The pressure rating will be cast into the wheel. Also not sure why one would run their 'G' rated tire underinflated at 80psi when pressure requirement for that tire is 120psi. The more underinflated you run the tires the more heat that builds up which is the cause of MANY tire failures. 'E' rated GY Marathons required 80psi, I ran them at 80psi, 'G' rated GY G614's require 120psi, run them at 120psi. You can run them a few lbs under max but NOT 20-40# under. Tim

G614's require 110 lbs not 120. OP's right near the time they upgraded wheels, so he should check them. G614 is about the same size as the Maratbomb. Sailun is one inch larger.

Chris