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Size 18.5-- RubberMaster Trailer Tires

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RubberMaster S368 (P815) 18.5X8.50-8 B/4PLY

489000 RubberMaster S368 (P815) 18.5X8.50-8 B/4PLY Tires

Rims Not Included

Trailer - Bias
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easy test score

8.0 Excellent

Per Tire:

$30.22

OR

$Loading /mo

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Was $37.78

Strikethrough Pricing on Giga Tires

Our percentage-off promotions, discounts, or sale markdowns are customarily based on our own opinion of the value of this product, which is not intended to reflect a former price at which this product has sold in the recent past. This amount represents our opinion of the full retail value of this product today, based on our own assessment after considering a number of factors.

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Please contact customer support. (877) 709-4442

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OR

$ /mo

Strikethrough Pricing on Giga Tires

Our percentage-off promotions, discounts, or sale markdowns are customarily based on our own opinion of the value of this product, which is not intended to reflect a former price at which this product has sold in the recent past. This amount represents our opinion of the full retail value of this product today, based on our own assessment after considering a number of factors.

RubberMaster S368 (P815) 18.5X8.50-8 C/6PLY

489020 RubberMaster S368 (P815) 18.5X8.50-8 C/6PLY Tires

Rims Not Included

Trailer - Bias
See details

easy test score

8.0 Excellent

Per Tire:

$32.77

OR

$Loading /mo

Save $

Lightning Savings

Was $40.96

Strikethrough Pricing on Giga Tires

Our percentage-off promotions, discounts, or sale markdowns are customarily based on our own opinion of the value of this product, which is not intended to reflect a former price at which this product has sold in the recent past. This amount represents our opinion of the full retail value of this product today, based on our own assessment after considering a number of factors.

1 tire
2 tires
3 tires
4 tires
5 tires
6 tires
7 tires
8 tires
9 tires
10 tires

Please contact customer support. (877) 709-4442

Estimated Delivery

Loading

Shipping

Loading

Installation available

Total

Loading

OR

$ /mo

Strikethrough Pricing on Giga Tires

Our percentage-off promotions, discounts, or sale markdowns are customarily based on our own opinion of the value of this product, which is not intended to reflect a former price at which this product has sold in the recent past. This amount represents our opinion of the full retail value of this product today, based on our own assessment after considering a number of factors.

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Airloc (1)
Carlisle (2)
Deestone (2)
Greenball (1)
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Nanco (1)
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RubberMaster (2)

Trailer (2)
Trailer - Bias (2)

B/4PLY (1)
C/6PLY (1)

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The lifespan of a tire based on wear performance
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At Giga Tires, we’ve delivered unbeatable tire prices and service since 2014. With over 1 million tires sold, a #9 ranking in Newsweek’s America’s Best Online Shops for 2026, and 34K+ 5-star ratings, we offer over 45K+ products along with great promotions, discounts, and rebates. Enjoy fast shipping to your home or a local installer like PepBoys, Monro, and TireChoice. Backed by a 45-day return policy, we make tire buying simple, reliable, and affordable. Headquartered in California, we proudly serve drivers across the continental US.

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