what are the stock r&p ration and gear ratios for a old style swing axle. thanks bill
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what are the stock r&p ration and gear ratios for a old style swing axle. thanks bill
Most of the later 1500/1600 powered cars came with a 4:12 R&P I believe.....That would be 1967 on....
Here's an article that will help to explain:
With the case design and the 2 prefix letters on the bottom, MOST transmissions tell their story without you having to take them apart. All of the old swingaxles up to 66-67, have a 4.37 R&P and a VERY weak first gear. Also, they have the 11 tooth (weaker) spider gears, But all of these older swingaxles have a steel 1st/2nd shifting fork.(stronger for "quicker" shifting) ("Speed" shifting will make a short life out of a VW tranny). From 67-up, swingaxles have a 4.12 R&P with a "better" first gear, the same weaker 11 tooth spider gears, and a brass shifting fork (not for ANY speed shifting!!!) IRS- All Irs trannies with the prefix code AH on the bottom left "corner" have a 4.12 R&P with the same "fair" first gear as the later model (12 volt) swingaxles, AND the brass 1st/2nd shifting fork, and 11 tooth spider gears. MOST (not all) of these will also have the two unboltable diff. covers. IRS trannies with the Prefix code of AT have a 3.88 R&P, bigger and better(10 tooth) spider gears, a stronger 1st gear(3.78 ratio), and a wider 1st/2nd shifting fork. Some are brass, and some are steel, you cannot know unless you take it apart, however, even the brass ones in these trannies are fairly strong. MOST (again there are a few exceptions) have a ONE side unboltable diff. cover. IRS trannies with a prefix of AV are a mix. They are out of the VW "thing" and have the 10 tooth spider gears, a 4.12 R&P, the strong 3.78 first gear, and output flanges that accept the type 2 cv joints. These are a tough trans in its stock form, especially for an IRS. There are a couple others and I will post them soon.
With the case design and the 2 prefix letters on the bottom, MOST transmissions tell their story without you having to take them apart. All of the old swingaxles up to 66-67, have a 4.37 R&P and a VERY weak first gear. Also, they have the 11 tooth (weaker) spider gears, But all of these older swingaxles have a steel 1st/2nd shifting fork.(stronger for "quicker" shifting) ("Speed" shifting will make a short life out of a VW tranny). From 67-up, swingaxles have a 4.12 R&P with a "better" first gear, the same weaker 11 tooth spider gears, and a brass shifting fork (not for ANY speed shifting!!!) IRS- All Irs trannies with the prefix code AH on the bottom left "corner" have a 4.12 R&P with the same "fair" first gear as the later model (12 volt) swingaxles, AND the brass 1st/2nd shifting fork, and 11 tooth spider gears. MOST (not all) of these will also have the two unboltable diff. covers. IRS trannies with the Prefix code of AT have a 3.88 R&P, bigger and better(10 tooth) spider gears, a stronger 1st gear(3.78 ratio), and a wider 1st/2nd shifting fork. Some are brass, and some are steel, you cannot know unless you take it apart, however, even the brass ones in these trannies are fairly strong. MOST (again there are a few exceptions) have a ONE side unboltable diff. cover. IRS trannies with a prefix of AV are a mix. They are out of the VW "thing" and have the 10 tooth spider gears, a 4.12 R&P, the strong 3.78 first gear, and output flanges that accept the type 2 cv joints. These are a tough trans in its stock form, especially for an IRS. There are a couple others and I will post them soon.
to larry jowdy. thanks for the info on trans axle i have old style the numbers on side of case are 3712 or 37/2 can you tell me what the rarios are it is not the 388. thanks bill