Dodge Cummins Diesel Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
243 Posts
Discussion Starter #1
I finally decided I want to get the Ridge Grappler. Now the Big decision is the size. what I am looking for is the actual measurement with a tape measure of the tire height when installed on the truck for two tires.

37/12.50/18= (35.5 tall?) this is a guess
35/12.50/18= (33.5 tall?) this is a guess

I am currently running a Toyo MT 315/70/18 and It measures (with 1/4 tread left) 34" tall. with 18x10 rims.

I have a 6" lift (I think, it was in the truck when I bought it.) I really that interested in getting a 35 if it only measures 33" tall. It may look too small.

any info will help.

Thanks,

Justin :grin2:
 

·
Registered
Joined
·
243 Posts
Discussion Starter #2
I finally decided I want to get the Ridge Grappler. Now the Big decision is the size. what I am looking for is the actual measurement with a tape measure of the tire height when installed on the truck for two tires.

37/12.50/18= (35.5 tall?) this is a guess
35/12.50/18= (33.5 tall?) this is a guess

I am currently running a Toyo MT 315/70/18 and It measures (with 1/4 tread left) 34" tall. with 18x10 rims.

I have a 6" lift (I think, it was in the truck when I bought it.) I really that interested in getting a 35 if it only measures 33" tall. It may look too small.

any info will help.

Thanks,

Justin :grin2:
This is for my 08 that I have. I meant to post in that section sorry.
 

·
Premium Member
Joined
·
2,474 Posts
Most 35's are going to be 34.5 and 37's will be closer to 36.5 not 33.5 and 35.5.
With a 6" lift you can it 37's without problem.

My leveled 2012 came with 35's on it when I bought it, and I think they look small.
 

·
Registered
Joined
·
243 Posts
Discussion Starter #4
Another member on here (ADay73) replied to me on here saying that his 37/12.50/18 measure 35.5 tall when installed on his truck.

I just want to make sure before I buy a tire that I don't like (shorter than what I have now). I will be happy with a tire that measures real close to 35" tall since my tires I have now measure out at 34" tall.

I have an 04 with a six inch lift that I have 37" Toyo's on, I think those measure out right around that 35.5 tall. Its been awhile since I checked them out.
 

·
Premium Member
Joined
·
2,474 Posts
Another member on here (ADay73) replied to me on here saying that his 37/12.50/18 measure 35.5 tall when installed on his truck.

I just want to make sure before I buy a tire that I don't like (shorter than what I have now). I will be happy with a tire that measures real close to 35" tall since my tires I have now measure out at 34" tall.

I have an 04 with a six inch lift that I have 37" Toyo's on, I think those measure out right around that 35.5 tall. Its been awhile since I checked them out.
That's rather strange, as the manufacturers information list the tire heights and say for a 35x12.5, depending on manufacturer and tire model they are typically 34.4x to 34.6x so usually saying 34.5 is pretty safe give or take a tenth or so.
So if your 37" Toyo's are only 35.5 that would be false advertising.
I've had my eye on the 37" Ridge Grapplers, which IIRC are listed at 36.67.
 

·
Registered
Joined
·
4,532 Posts
When loaded any tire is going to be shorter than it is wide. A 35 will be about 34.5 across but only about 33.5 tall. It's that flat spot on the bottom. Most tires are about 90% of unloaded height when loaded.

Sent from my SM-G920T using Tapatalk
 

·
Premium Member
Joined
·
2,474 Posts
When loaded any tire is going to be shorter than it is wide. A 35 will be about 34.5 across but only about 33.5 tall. It's that flat spot on the bottom. Most tires are about 90% of unloaded height when loaded.

Sent from my SM-G920T using Tapatalk
I suppose an inch of tire "squish" is possible. Depending on inflation PSI.
However 90% would mean 10% squish on a 34.5" tire would be 3.45" squish. That would be a flat tire !
The math would work out closer to 97%
 

·
Registered
Joined
·
243 Posts
Discussion Starter #8
That's rather strange, as the manufacturers information list the tire heights and say for a 35x12.5, depending on manufacturer and tire model they are typically 34.4x to 34.6x so usually saying 34.5 is pretty safe give or take a tenth or so.
So if your 37" Toyo's are only 35.5 that would be false advertising.
I've had my eye on the 37" Ridge Grapplers, which IIRC are listed at 36.67.
Don't quote me on my Toyo 37" I will have to double check them when I get home in a week. maybe they do measure 36. but it seams every single tire I get does not come close the advertised height. My favorite is Toyo MT so far. I have had 3 sets. That Ridge Grappler has really caught my eye as well. if the 35/12.50/18 actually measures 34 to 34.5 I would get those for sure. if they are shorter I will have to get the 37. some one on here should have those on here I would think.
 

·
Registered
Joined
·
4,532 Posts
Don't quote me on my Toyo 37" I will have to double check them when I get home in a week. maybe they do measure 36. but it seams every single tire I get does not come close the advertised height. My favorite is Toyo MT so far. I have had 3 sets. That Ridge Grappler has really caught my eye as well. if the 35/12.50/18 actually measures 34 to 34.5 I would get those for sure. if they are shorter I will have to get the 37. some one on here should have those on here I would think.
Your correct I was thinking rolling diameter which runs between 90-95% of unloaded depending on tire profile. Static height only affects one radius so it would be closer to 95-97%.

Sent from my SM-G920T using Tapatalk
 

·
Registered
Joined
·
39 Posts
just go to the manu site and look up the specs under 'more details'. dont need to measure your tires with a tape! all tires will squish about the same as long as they are matched for the load.
 

·
Registered
Joined
·
243 Posts
Discussion Starter #11
just go to the manu site and look up the specs under 'more details'. dont need to measure your tires with a tape! all tires will squish about the same as long as they are matched for the load.
I aware of the spec section. For different tire manufactures, tire size varies. I have gone through many sets of tires and many different sizes. They do not measure up to what the spec says on the web site. the only tire that I had about 10yrs ago that came close the advertised size was a Pro-Comp Xtreme A/t. 37/13.50/20 it measured with a tape at 36.5" when installed on the truck, I got a lot of miles out of that set of tires. 65k.
 

·
Registered
Joined
·
39 Posts
I aware of the spec section. For different tire manufactures, tire size varies. I have gone through many sets of tires and many different sizes. They do not measure up to what the spec says on the web site. the only tire that I had about 10yrs ago that came close the advertised size was a Pro-Comp Xtreme A/t. 37/13.50/20 it measured with a tape at 36.5" when installed on the truck, I got a lot of miles out of that set of tires. 65k.
I hear ya now. how the heck to measure them consistently! front gonna be more out of round than rear due to weight. And then there is tread wear factor.
Unless you jack up tire and fill to max psi and measure circumference and do the math.
I think the manu specs are dead on anymore thanks to lawyers.
 

·
Registered
Joined
·
243 Posts
Discussion Starter #13
I whent with the 37’s hopefully will get them on in a week.
 

·
Registered
Joined
·
39 Posts
Pls keep us all posted on your reviews and impressions. And good luck!
I was talking yesterday to the manager of our local les schwab store down here in so oregon. he is a friend so so no bs. Said there are a bunch of guys who have been eyeballin that tire but noone has seen them locally and noone wants to be the guinea pig. We have all found the toyo m/t to be the most durable all around tire for the heavy cummins front end. We also know that it wears even if not in the reverse ie: as the tread wears down the wear slows down some. But for a pair of 37x13.5 its 2 grand mounted so we are all waiting for the other guy to buy and try!

My toyos are at 63% tread so for me the tires are on their last 1/4 of life. I might sipe them at 45 degrees and run em thru the winner and spring.
 

·
Registered
Joined
·
243 Posts
Discussion Starter #15
The cost definitely goes up slightly when you go to a 37! :)
I am hoping to get them on in a week. They are in at the shop but won’t have time to install for another week. I will keep posted in here for a review.
 

·
Registered
Joined
·
10,323 Posts
The specs are set on an inflated tire mounted on an approved rim off of the vehicle is what I understand.
 

·
Registered
Joined
·
583 Posts
Go with the 37" if you have a 6" lift 35's will look too small... Personally I think the 37's look a little small.

Just measured my 37x13.50R17 M/T's with a tape. 35.5 inches tall, 13ish inches wide. 50ish psi no load and about 30% tread. Got 60k on them...
 

·
Registered
Joined
·
71 Posts
Not to be a PITA here, but measuring tire height mounted on the truck vs manufacturer specs are going to be about as much different as what you're all saying measurement-wise. For example, my 295/65R20's a hair over 35" according to specs, and sitting on the sidewall they measure as such. Mounted on my truck with 8.5k+lbs sitting on them @~50PSI they measure damn near 34". Gravity is a ..
 

·
Registered
Joined
·
243 Posts
Discussion Starter #20
I went with 37’s. They are sitting on my brother in laws shop floor. He sent me a pic of them. Damn it I will not get to put them on till next weekend. So for now I just stare at the picture.
 
1 - 20 of 21 Posts
Top