Truck Wheel Size

[River_Hill]

Looking at some new trucks and have the option of 17", 18" or 20" wheels. Any reason to go with one over the other? I think the 17" might do a little better off-road as the tire would have more flex.

[Me_Again]

8.1 Van wrote:
It looks like most 17" tires top out at 3,195 lb capacity but if you go up to a LT295/70R18 it has a capacity of 4,080 lbs @80psi.

OEM wheels most likely are not rated that high. I believe the RAM Laramie 18" wheels are rated at 3500.

Chris

[8_1_Van]

It looks like most 17" tires top out at 3,195 lb capacity but if you go up to a LT295/70R18 it has a capacity of 4,080 lbs @80psi.

[Me_Again]

8.1 Van wrote:

Me Again wrote:

8.1 Van wrote:

Flashman wrote:
20 inch wheels are for show. They are stupid for trucks that really do any real work.

If you want high capacity the LT295/65R20E tires have a 4,080lb capacity that is higher than most 18, 17 or 16" tires.

On a RAM with 3:42 gears going from a 33.19 diameter tire to a 35.1 would not be the best idea. These trucks already have long legs.

If you want high capacity in a short tire for better gearing the 285/65R16C load range E has a 3,970 lb capacity @85psi and is only 30.6" tall.

As noted earlier, newer trucks require at least 17" rims to clear the caliper.

[8_1_Van]

Me Again wrote:

8.1 Van wrote:

Flashman wrote:
20 inch wheels are for show. They are stupid for trucks that really do any real work.

If you want high capacity the LT295/65R20E tires have a 4,080lb capacity that is higher than most 18, 17 or 16" tires.

On a RAM with 3:42 gears going from a 33.19 diameter tire to a 35.1 would not be the best idea. These trucks already have long legs.

If you want high capacity in a short tire for better gearing the 285/65R16C load range E has a 3,970 lb capacity @85psi and is only 30.6" tall.

[IdaD]

ShinerBock wrote:

IdaD wrote:


You didn't pick the wheels you wanted? It isn't hard to find manufacturer weight ratings on wheels. It is important, though, because some 18" wheels are rated lower than the 3640 lbs on the tires.

I agree with all the comments saying 18" is ideal on the newer HD models. 17" aren't rated as well and 20" are more expensive and have a more limited selection.

Nope. In fact, I didn't even see them until they pulled the truck around when they were finished. I didn't care too much what they looked like as long they met or exceeded the load rating, somethign that I didn't have to clean all the time, and did not scream "I am a 17 year old with white Oakley's driving a pavement queen". I believe those were my exact words to him. They ended up being black MB 352's and look pretty good on the truck while meeting my requirements so I was happy.

Not a bad outcome I guess although the fake beadlocks have always been a bit of a pet peeve of mine on a lot of truck wheels.

[Grit_dog]

8.1 Van wrote:

Flashman wrote:
20 inch wheels are for show. They are stupid for trucks that really do any real work.

If you want high capacity the LT295/65R20E tires have a 4,080lb capacity that is higher than most 18, 17 or 16" tires.

I’ve got some 275-65-20s on the truck now for the winter. 126 or 3750lb load rating, plenty of sidewall and $760 delivered to my door last year. Seem to fit the bill all around.
Barely taller than stock (although I could use 35s or even 37s with my truck to keep rpms down), great load capacity and cheap.

[Grit_dog]

^But you could have just run the spare, correct?

Some of these comments are absoulutly laughable. Cost for a comparable size tire aside, the real world differences are almost nil. Save for the bigger rims allowing for a little less sidewall flex for a same given tire diameter.
I bet some of your fathers complained when they did away with good ole split rims too!

[tomman58]

Me Again wrote:

tomman58 wrote:
I have 20" now on my 2015 GMC would go back to 18" because truck is to high for my wife and others and ALSO THE TRUCK HAS AN 18" SPARE!!!!!!!
Who would've thought that the spare is not totally interchangeable?

Check the tire radius, and you will find them similar.

RAM uses LT275/70R18 with diameter of 33.19
and LT285/60R20 with diameter of 33.46

So .27 /2 = .135 difference in radius, so I do not think about an 1/8 inch would be very noticeable getting in and out of the truck.

These numbers on based on OEM Firestone Transforce AT's. Other brands will be similar.

What happened was I broke a belt in one of my tires and wanted to put the spare tire on the 20" rim. Couldn't do it and had to pay for new tire at a place that wasn't cost effective.

Chris

[Me_Again]

8.1 Van wrote:

Flashman wrote:
20 inch wheels are for show. They are stupid for trucks that really do any real work.

If you want high capacity the LT295/65R20E tires have a 4,080lb capacity that is higher than most 18, 17 or 16" tires.

On a RAM with 3:42 gears going from a 33.19 diameter tire to a 35.1 would not be the best idea. These trucks already have long legs.

[8_1_Van]

Flashman wrote:
20 inch wheels are for show. They are stupid for trucks that really do any real work.

If you want high capacity the LT295/65R20E tires have a 4,080lb capacity that is higher than most 18, 17 or 16" tires.

[ShinerBock]

IdaD wrote:


You didn't pick the wheels you wanted? It isn't hard to find manufacturer weight ratings on wheels. It is important, though, because some 18" wheels are rated lower than the 3640 lbs on the tires.

I agree with all the comments saying 18" is ideal on the newer HD models. 17" aren't rated as well and 20" are more expensive and have a more limited selection.

Nope. In fact, I didn't even see them until they pulled the truck around when they were finished. I didn't care too much what they looked like as long they met or exceeded the load rating, somethign that I didn't have to clean all the time, and did not scream "I am a 17 year old with white Oakley's driving a pavement queen". I believe those were my exact words to him. They ended up being black MB 352's and look pretty good on the truck while meeting my requirements so I was happy.

[IdaD]

ShinerBock wrote:
When I bought my truck, one of the first things I did was trade out the factory tires for better off road tires. It gets a little sloppy at the farm and deer lease when it rains. My truck came with 20's and the Nitto Trail Grappler tire I wanted was $80 per tire more for a 20" versus an 18".

Not being fond of 20" tires in general, I asked the tire store to put any 18" rim on the truck that the had in inventory that met my stock rim load ratings. The 18" rims cost me about $140 each and I ended up selling my stock 20" rims for $150 each.

You didn't pick the wheels you wanted? It isn't hard to find manufacturer weight ratings on wheels. It is important, though, because some 18" wheels are rated lower than the 3640 lbs on the tires.

I agree with all the comments saying 18" is ideal on the newer HD models. 17" aren't rated as well and 20" are more expensive and have a more limited selection.

[ktmrfs]

tomman58 wrote:
I have 20" now on my 2015 GMC would go back to 18" because truck is to high for my wife and others and ALSO THE TRUCK HAS AN 18" SPARE!!!!!!!
Who would've thought that the spare is not totally interchangeable?

1_ the Spare has very very very close to the same diameter at the 20 inch, and a slightly higher load capacity.
2) if it is a 3/4 or 1 ton, 18" will the ride height will be exactly the same with factory 18" tires.

[Me_Again]

tomman58 wrote:
I have 20" now on my 2015 GMC would go back to 18" because truck is to high for my wife and others and ALSO THE TRUCK HAS AN 18" SPARE!!!!!!!
Who would've thought that the spare is not totally interchangeable?

Check the tire radius, and you will find them similar.

RAM uses LT275/70R18 with diameter of 33.19
and LT285/60R20 with diameter of 33.46

So .27 /2 = .135 difference in radius, so I do not think about an 1/8 inch would be very noticeable getting in and out of the truck.

These numbers on based on OEM Firestone Transforce AT's. Other brands will be similar.

Chris