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Christ · 06-13-2010, 01:14 AM

In some cases, it's a bad idea to set toe-in to 0 on an idle truck because of "scrub angles" of the tires.

Not saying this is the case with your truck, but the proper way to dial in the toe for the least drag at a given speed would be to measure the average suspension height at that speed, and set it so that suspension travel and scrub angle sets the tire to 0 toe at the speed you want.

IE if you hold 75, figure out where your suspension is on average at 75 on a flat, smooth, level road (yeah, right), and determine 0 toe for that suspension load, and then (I have no idea how to do this part) calculate the angular load against the tires for that speed and set the toe inward enough to combat it at that speed.

However: This may not apply to your truck. I don't know if toe angles are changed with I-beam front suspension and a non-R/P steering setup. I don't think they are. Scrub angle still applies, though, for the record.

06-13-2010, 01:14 AM	#6 (permalink)
Christ Moderate your Moderation. Join Date: Nov 2008 Location: Troy, Pa. Posts: 8,919 Pasta - '96 Volkswagen Passat TDi 90 day: 45.22 mpg (US) Thanks: 1,369 Thanked 430 Times in 353 Posts	In some cases, it's a bad idea to set toe-in to 0 on an idle truck because of "scrub angles" of the tires. Not saying this is the case with your truck, but the proper way to dial in the toe for the least drag at a given speed would be to measure the average suspension height at that speed, and set it so that suspension travel and scrub angle sets the tire to 0 toe at the speed you want. IE if you hold 75, figure out where your suspension is on average at 75 on a flat, smooth, level road (yeah, right), and determine 0 toe for that suspension load, and then (I have no idea how to do this part) calculate the angular load against the tires for that speed and set the toe inward enough to combat it at that speed. However: This may not apply to your truck. I don't know if toe angles are changed with I-beam front suspension and a non-R/P steering setup. I don't think they are. Scrub angle still applies, though, for the record. __________________ "¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"