Rear End Question

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goodnigh

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My Marti report reads my rear end is a "standard axle ratio 3.25",  9 on the door plate.

This is an M-code w/toploader and comp suspension, I thought all configurations like 

that came with a 3.50 and Trak-Loc.  The Eminger invoice makes no mention of the rear.

mike

 
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My Marti report reads my rear end is a "standard axle ratio 3.25",  9 on the door plate.

This is an M-code w/toploader and comp suspension, I thought all configurations like 

that came with a 3.50 and Trak-Loc.  The Eminger invoice makes no mention of the rear.

mike
Mine is exactly the same. It would have been nice if Ford did put the 3.50:1 Traction-lock in the M code configuration. Ford did a lot of weird things back then that make no sense today.

 
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Hello goodnigh,

Back in "Those" days the option book  was your (and Fords) friend. In '71 the Boss 351 and 429's with the Drag Pack option were the only models that had Traction -Lok standard. The differential ratios were based on how the vehicle was equipped. The biggest limiting factor was AC equipped models,  which  were limited to 3.25.  Although Ford info shows 3.25 as the maximum gear with AC equipped '71 "Q" 351CJ's,  some owners have reported  having the "S" 3.50 Traction-Lok gear on their AC equipped '71 Q's.

The Traction-lok option was $48.00 (308.42 today) and the optional ratio gear was $13.00 (83.53 today) so still a bargain regardless of year!

@ Geoff, back in the late '70s I had a '71 M 4sp Mach1 (no AC) that was equipped with a Traction-lok 3.50. That car was an absolute blast to drive and kept my tire budget shredded. There were some good performance combinations available, you just had to be knowledgeable on how to negotiate Ford's confusing corn maize of ordering perimeters  and a  helpful sales person.    :classic_smile:

 
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Hello goodnigh,

Back in "Those" days the option book  was your (and Fords) friend. In '71 the Boss 351 and 429's with the Drag Pack option were the only models that had Traction -Lok standard. The differential ratios were based on how the vehicle was equipped. The biggest limiting factor was AC equipped models,  which  were limited to 3.25.  Although Ford info shows 3.25 as the maximum gear with AC equipped '71 "Q" 351CJ's,  some owners have reported  having the "S" 3.50 Traction-Lok gear on their AC equipped '71 Q's.

The Traction-lok option was $48.00 (308.42 today) and the optional ratio gear was $13.00 (83.53 today) so still a bargain regardless of year!

@ Geoff, back in the late '70s I had a '71 M 4sp Mach1 (no AC) that was equipped with a Traction-lok 3.50. That car was an absolute blast to drive and kept my tire budget shredded. There were some good performance combinations available, you just had to be knowledgeable on how to negotiate Ford's confusing corn maize of ordering perimeters  and a  helpful sales person.    :classic_smile:
 Steve, I do know that the 3.50:1 was available, but the car I ended up with apparently was ordered with practically no options. According to Marti, there were 6 identical, but I have no idea if they were all ordered by the same dealership in Santa Rosa Ca. I guess someone forgot to look at the "options" sheet. What I meant was it would have been nice if Ford offered ALL M code 4 spd Mach's with 3.50:1 gears as standard and with the 3.25:1 offered for A/C cars. To me, that would have made more sense......... Oh wait, it's Ford we're talking about here, sorry.

 
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Hello Geoff, now your catching on. I was raised in an all-Ford family and am a dictionary example of a Ford fanatic. So with that and my dealer experience, I'm used to the disconnect between decisions made at the "Glass House" (Ford World Headquarters) and us commoners!
As confusing as dealing with one car line as we do here, just imagine the poor sales staff dealing with all the car and truck lines and the endless possibilities when trying to order that perfect vehicle. The confusion and nonsense was an equal opportunity employer. Back in the '80s, a Chevy friend wanted to order a new family vehicle. He wanted cruise control, but had to order rocker panel moldings in conjunction with the cruise!?? That meant drilling holes in the rocker panel for the fasteners that held the molding. Perfect for a northern car that would experience salt spray in the rocker area. I believe the car was a Citation which would rust and break in half just sitting in the driveway.
I agree with Carolina_Mountain_Mustang that the Mach 1 should have had more performance-oriented equipment standard instead of just stripes. Geoff's wish list would be a good start. (M code, 4sp or AT with a 3.50 gear)   :classic_smile:

 

Hemikiller

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The 71, 72 and 73 Facts book have a chart that shows all the available powertrains combos. Here's the one from the 71.

71powertrain.jpg

 
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goodnigh

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Interesting read.  So Ford decided what rear end to put in the car.

I noticed the M-code vert auto came with a 3.00 if it had air.

Who makes those decisions, based on what?  If you have an M-code

you want to be able to use it.

mike

 
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Hello Geoff, now your catching on. I was raised in an all-Ford family and am a dictionary example of a Ford fanatic. So with that and my dealer experience, I'm used to the disconnect between decisions made at the "Glass House" (Ford World Headquarters) and us commoners!
As confusing as dealing with one car line as we do here, just imagine the poor sales staff dealing with all the car and truck lines and the endless possibilities when trying to order that perfect vehicle. The confusion and nonsense was an equal opportunity employer. Back in the '80s, a Chevy friend wanted to order a new family vehicle. He wanted cruise control, but had to order rocker panel moldings in conjunction with the cruise!?? That meant drilling holes in the rocker panel for the fasteners that held the molding. Perfect for a northern car that would experience salt spray in the rocker area. I believe the car was a Citation which would rust and break in half just sitting in the driveway.
I agree with Carolina_Mountain_Mustang that the Mach 1 should have had more performance-oriented equipment standard instead of just stripes. Geoff's wish list would be a good start. (M code, 4sp or AT with a 3.50 gear)   :classic_smile:
Steve, My wish list, wouldn't it. But it is what it is now, we're just 50 years too late.

Back in the UK at that time, we were lucky if we had a car with enough power to get up a small hill, let alone strip rubber!!

 
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Interesting read.  So Ford decided what rear end to put in the car.

I noticed the M-code vert auto came with a 3.00 if it had air.

Who makes those decisions, based on what?  If you have an M-code

you want to be able to use it.

mike
Who made those decisions? If you ask me, a bean counter or some other dweeb with absolutely no interest or knowledge of cars and the car culture. 

Like I replied to Steve, we're just 50 years too late to the party. 

 
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The drive train options by the 70's had dropped due to government requirements to pass I believe a 40,000 mile track test. So if you had 15 different combos you had to run 15 cars for 40,000 miles on test track. You can now understand why those options dropped. That is 40,000 miles without touching the car. That is why the ram air was dropped for the 4-V someone did a tune up on that test car so it would have to start all over so Ford said no just not an option.

 
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