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HELP, over GVWR BY 400 lbs.

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OggyOggy

What's NORMAL and HOT in a differential temperature?

  • OggyOggy
  • Replies: 1
B

Brake pads

  • Bossman
  • Replies: 22
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I think about what I paid. I recall spending right under $1K for 5 of them.

Bridgestone and Toyo get good reviews. I run Toyo M608z's but they are more aggressive than I need and will go with a closed shoulder tire next time.

They will probably stick out about 1" more than the OEM wheels.
 
dfb said:
Excellent!. Thank you snoking!
Click to expand...

I added more info in the post above. Wheels are available is black also.

I think this expensive Michelin XDS 2 would be my choice based on tread pattern. They are however .5" larger in diameter.

#ad
 
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That tire is really too tall for the gearing. Would be really good for 3.73's but anything less than 70-75 mph is going to put the engine in the idle range in high gear. With a heavy load that combo will be leverage challenged.

A little overkill for weight on an SRW.
 
Most 245/70R19.5's are right around 624 rev/mile. The OEM 18" tire is 630. It's a negligible change.

I agree it's taller than wanted for towing with 3.42's on 6th, but not any different than what he is doing now.
 
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That is about a 1" difference in height from stock. On 4.10's it would be negligible, on 3.42's that is a big jump. Overkill for weight handling but they should be a solid tire.
 
No it's not a 1" difference. Stock is 275/70R18 with the 7K axle rating. That's a 630 rev/mile tire. 245/70R19.5'a are generally 624 rev/mile.

0.95% larger is negligible.
 
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A 275/70R18 is 33.3" tall, the listed tire is 34" tall. That is actually a 3.2% difference. Less than 1% would be insignificant, more than 3 is highly significant especially given the final drive ratio.

The percentage differences do not tell the whole story as the relationship is NOT linear. The lower the gears the less the actual change, as I said with 4.10's 2-3 inches is getting significant, with 3.73's 1" is significant, at 3.55's it is even more significant. The size difference is also dependent on where it starts. With 3.73's a change from 31" to 33" is not significant. However, that same change from 33" to 34" is much more significant.
 
cerberusiam said:
A 275/70R18 is 33.3" tall, the listed tire is 34" tall. That is actually a 3.2% difference. Less than 1% would be insignificant, more than 3 is highly significant especially given the final drive ratio.

The percentage differences do not tell the whole story as the relationship is NOT linear. The lower the gears the less the actual change, as I said with 4.10's 2-3 inches is getting significant, with 3.73's 1" is significant, at 3.55's it is even more significant. The size difference is also dependent on where it starts. With 3.73's a change from 31" to 33" is not significant. However, that same change from 33" to 34" is much more significant.
Click to expand...

Static height means nothing when you are moving.. hence the difference in revolutions per mile is only 0.95% (based on average sizes) and negligible.
 
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Those Michelin's are big for a 245/70R19.5. Most of them are in the 622-626 range.

My comment was a general comment based on 624 as it's the most common I size I have seen, as well as a good average.

Even at 615 it's a 2.4% change and still not the 3.2% stated above.


The Michelin's are also a LRG and that's a lot more than most need, heck even LRF is more than most need.

Newsa said:
245 × 0.7 x 2 ÷ 25.4 + 19.5 = 33 inches. It's not 34 inches tall
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That will give you a general idea; however, published specs are the way to go. As you can see with SNOKING's link there are differences in tires all with the same size.

Just looking at the XDS2 I see 3 sizes.

Sidewall size: 33"
Published size: 33.6"
Rolling Diameter (the important one): 32.8"

The OEM 275/70R18's are Firestone Transforce HT's

Sidewall: 33.15"
Published: 33.1"
Rolling: 32.0"


To compare the difference in the OEM 18's and 245/70R19.5's I ran some numbers. I sampled 45, 55, 65, and 75 mph in 4th, 5th, and 6th gear of an AE G56 with 3.42's. Across the board there was less than 30 rpm difference, that's pretty negligible IMHO. Some of the differences were as low as 9 rpms, 6th gear at 45.




EDIT: It appears RAM has updated their tire sizing. The 20" OEM combo is now 626 and the 18" combo is now 630. I edited the above posts to reflect that minor change. It appears that Firestone has 2 different 275/70R18's. One at 627 (Ram used 626) and one at 630. I am unsure of the purpose behind the difference.
 
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Newsa said:
245 × 0.7 x 2 ÷ 25.4 + 19.5 = 33 inches. It's not 34 inches tall
Click to expand...

APPROXIMATE size not actual, depends on the tire and the width of rim it is installed.

The Michelin is listed as a 34" tire, the stock tire as 33.2". The real difference will be somewhere between depending on rim widths. The impact of going from a 33" to a 34" tire as measured on the vehicle with 3.73 gears is significant for performance, both accelerating and maintaining speed.

With higher ratios the impact increases, that is the way the physics works. The real test will be actual application on the vehicle, then, no matter what the numbers say it becomes evident.
 
cerberusiam said:
APPROXIMATE size not actual, depends on the tire and the width of rim it is installed.

The Michelin is listed as a 34" tire, the stock tire as 33.2". The real difference will be somewhere between depending on rim widths. The impact of going from a 33" to a 34" tire as measured on the vehicle with 3.73 gears is significant for performance, both accelerating and maintaining speed.

With higher ratios the impact increases, that is the way the physics works. The real test will be actual application on the vehicle, then, no matter what the numbers say it becomes evident.
Click to expand...

No need to guess.. Rev/mile IS the rolling diameter that should be used for comparison.

Where are you finding 34"? Michelin lists it as 33.6", for a 0.4" difference than stock on static height. Rolling height is a 0.8" difference, which is likely due to the lack of sidewall flex on the LRG's. It's a much smaller rolling difference on standard sized 245/70R19.5's.
 
All this tire talk is, well.......making me hungry

POPCORNTHUMBSUP.JPG


POPCORNTHUMBSUP.JPG
 
Mingoglia said:
Here's my Mega Cab. This is weight with me in it AFTER my 20" stretch, with my 260lb butt in the drivers seat. Not sure what the stretch does to the steer weight.

View attachment 95420
Click to expand...

Holy crap!! That is pretty heavy on the front!! Did you check to see if there was a Prius stuck in the grill before you weighed??

The reason I ask is about a week ago I scaled my truck with a pretty heavy load and the front axle was only 4900lb!!
 
Mikey-KE7LBB said:
Holy crap!! That is pretty heavy on the front!! Did you check to see if there was a Prius stuck in the grill before you weighed??

The reason I ask is about a week ago I scaled my truck with a pretty heavy load and the front axle was only 4900lb!!
Click to expand...

Check your oil pan too. Had to scrape one of those off while ago. Or maybe it was a mini?
 
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Issue 128 – Digital Version
Digital Magazines
FREE!
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Subscribe
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Back Issues
Subscription Status
Address Change Form
Buyer's Guides
Ram Diagnostic Trouble Codes
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The Perfect Collection Vol. II
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What Makes Us Tick?
Product Showcase
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