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30 Closed Cab PU · 11-12-2019, 10:43 AM

I had my truck changed from 4.11 to 3.54. Am satisfied, but I drive lower speeds 45 mph is usually max. Motor is rebuilt, Standard head, but not balanced or built for touring. It will do 55-60, but is in the 2200 - 2400 rpm range maxed out, which personally I do not think is good for a standard motor, especially for more than a few minutes.

Most people who want to run higher speeds 55-60 use a high compression head, touring built motor, brakes and suspension/front end in tip top shape, radial tires, and a Mitchell overdrive with I believe 3.78 rear end (not 100% sure of 3.78). Quite a few also add an oil filter.

If you get the wrong component mix you may have OK speed/RPM, but be lacking in ability to take on hills without shifting way down (lack of torque). This is additional info on J Franklin's Post.

If going to a 3.24 rear end without a Mitchell, consider a high compression head, which also means the motor should be fairly fresh with good compression and Babbitt or Insert bearings to handle the extra load of higher compression and lower RPMs/loads.

11-12-2019, 10:43 AM	#3
30 Closed Cab PU Senior Member Join Date: Aug 2018 Posts: 2,332	Re: Gear ratio I had my truck changed from 4.11 to 3.54. Am satisfied, but I drive lower speeds 45 mph is usually max. Motor is rebuilt, Standard head, but not balanced or built for touring. It will do 55-60, but is in the 2200 - 2400 rpm range maxed out, which personally I do not think is good for a standard motor, especially for more than a few minutes. Most people who want to run higher speeds 55-60 use a high compression head, touring built motor, brakes and suspension/front end in tip top shape, radial tires, and a Mitchell overdrive with I believe 3.78 rear end (not 100% sure of 3.78). Quite a few also add an oil filter. If you get the wrong component mix you may have OK speed/RPM, but be lacking in ability to take on hills without shifting way down (lack of torque). This is additional info on J Franklin's Post. If going to a 3.24 rear end without a Mitchell, consider a high compression head, which also means the motor should be fairly fresh with good compression and Babbitt or Insert bearings to handle the extra load of higher compression and lower RPMs/loads.