3.73 for 4.11 gears swap

JCM

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Mar 22, 2020
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I need to set up a rig for my college kid to use as a daily driver and want to swap 3.73s in for the 4.11s that I have now. Set up with 350 SBC, 4 speed, 33" tires, but just need to get top speed up a little to make this more usable. I'm having a hard time sourcing parts - seems like a few of the guys that were selling these (front and back) are not to be found. I already know/understand the downside of swapping out the 4.11s but for my purposes I have determined that it is the way to go. Any direction on where to source 3.73s would be much appreciated.
 

pb4ugo

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Earlier FJ40 came with 4.11:1 gears in the differential. In 1979 Toyota change ratios to 3.70:1. You might be able to find used stk 3rd members with 3.70's and swap them in, or you can purchase aftermarket gears to what ever ratios you want. I think if you go aftermarket youll have to source fine spline pinion flanges with the proper bolt pattern for your driveshaft.
 

JCM

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Mar 22, 2020
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Texas
Thanks all! I finally stumbled upon Cruiser Outfitters website shortly after posting, and after giving them a call and emailing with tech, was able to buy a couple of master install kits as well as a couple of pairs of gears. Nice and easy. We will see how it goes from here, but looking forward to hopefully an additional 10% of top-end speed (I just don't want to think about how much each additional mph costs . . .).
 
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Let us know how it goes. I have a similar setup with a 327 and would like to get lower rpms at freeway speeds.
 

GA Architect

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Thanks all! I finally stumbled upon Cruiser Outfitters website shortly after posting, and after giving them a call and emailing with tech, was able to buy a couple of master install kits as well as a couple of pairs of gears. Nice and easy. We will see how it goes from here, but looking forward to hopefully an additional 10% of top-end speed (I just don't want to think about how much each additional mph costs . . .).
You will like the new 3:70's. I swapped out the original 4.11 in mine for a set of 3:70 gears. Top speed I reached, 85MPH (+/-) General cruising speed on the highway, 70MPH eazy.

1652579740097.png


Also, if you are using the OEM speedometer, it will be off when you swap the gears. I called Commercial Speedometer (916-371-5873) in Sacramento, CA to get a Correction Syncro box, and how to calculate correction ratio.

1652580042354.png
 

brian

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You will like the new 3:70's. I swapped out the original 4.11 in mine for a set of 3:70 gears. Top speed I reached, 85MPH (+/-) General cruising speed on the highway, 70MPH eazy.

View attachment 3009099

Also, if you are using the OEM speedometer, it will be off when you swap the gears. I called Commercial Speedometer (916-371-5873) in Sacramento, CA to get a Correction Syncro box, and how to calculate correction ratio.
If i figured right, its off 25% between the 33s and 370s in place of the 411s.
This has been one of the best things I've done to it....improved daily drive ability hugely.
 

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