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D13 · 01-29-2010, 12:31 PM

If it's truely a 14b SF 9.5" then the 'standard' ratio would be 3.42. The lowest numeric ratio would be a 3.23 (unusual) and the highest 4.56.

The standard ratio on my 81 3/4 with a L6 250 and 3OTT is a 3.42.

The term 'standard' means that the customer didn't order anything special. What was 'standard' varied with engine and trans. For example, a 454 in a half ton would get a different ratio than the same in a 3/4 ton, because it was assumed that the half ton was for occasional towing and the 3/4 ton was for heavy loads. Plus the differnece in the tire sizes and the torque capability in the axles which might restrict the gear ratios available.

01-29-2010, 12:31 PM	#4
D13 Registered User Join Date: Feb 2007 Location: Memphis MI Posts: 1,851	Re: RPO code GQ1 If it's truely a 14b SF 9.5" then the 'standard' ratio would be 3.42. The lowest numeric ratio would be a 3.23 (unusual) and the highest 4.56. The standard ratio on my 81 3/4 with a L6 250 and 3OTT is a 3.42. The term 'standard' means that the customer didn't order anything special. What was 'standard' varied with engine and trans. For example, a 454 in a half ton would get a different ratio than the same in a 3/4 ton, because it was assumed that the half ton was for occasional towing and the 3/4 ton was for heavy loads. Plus the differnece in the tire sizes and the torque capability in the axles which might restrict the gear ratios available. __________________ 1987 2 ton 1982 250/TH350 beater in progress Dad's 1981 3/4 L6 3 on tree posi and no options, awaiting restoration or scrapping Plus a mess o' tractors Last edited by D13; 01-29-2010 at 12:34 PM.