Re-gearing...
02-12-2006 | 01:50 PM
#1
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From: San Antonio, TX
Re-gearing...
In the future, I plan on doing an SAS and running 35" tires... 5.29's seems like the magic number for 35" tires... How much would it cost to re-gear my 1991 4runner to 5.29? Also, is it too high for my current 31" tires? Thanks, Eric
02-12-2006 | 01:56 PM
#2
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From: Solano Co, CA Originally a North Idaho Hick
Mine cost $1000 installed. I wouldn't want to run 5.29's at all with 31's. My rig turns 3300 rpm now at 70 mph with 4.88's and 33's. I'd imagine you'd be close to redline trying to run at freeway speeds.. I could be wrong though.
02-12-2006 | 02:26 PM
#4
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Maybe this link will help you determine your needs:
http://www.intercotire.com/site63.php
I'm not sure the 'yellow, green, red' system on that page is really helpful. But at least you can get a sense of engine RPM with various gears / tire sizes. The chart notes an assumed 1:1 final drive ratio in the tranny. If you have an automatic with overdrive ( typically 30% overdriven), multiply the RPMs by .7 to get relative 'highway' RPMs.
If you know your RPM's (at a 'true' 65 MPH ) with the tire/gear combo you currently have, you should be able to compare it to the change you'd prefer to make by looking at the chart.
Mike in AR
http://www.intercotire.com/site63.php
I'm not sure the 'yellow, green, red' system on that page is really helpful. But at least you can get a sense of engine RPM with various gears / tire sizes. The chart notes an assumed 1:1 final drive ratio in the tranny. If you have an automatic with overdrive ( typically 30% overdriven), multiply the RPMs by .7 to get relative 'highway' RPMs.
If you know your RPM's (at a 'true' 65 MPH ) with the tire/gear combo you currently have, you should be able to compare it to the change you'd prefer to make by looking at the chart.
Mike in AR
Last edited by regularguy412; 02-12-2006 at 02:28 PM.
02-12-2006 | 02:44 PM
#5
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From: San Antonio, TX
By the look of the yellow green red system, it's saying that yellow is better gas milage (lower rpm's), green is factory ratio (with a balance between power and efficiency), and that red is more power (much higher rpms).
The chart shows that my 4Runner would be running at around 3727 rpm's, which is way too high in my opinion. I only run the engine that high when I really need to get going, so I'd need to run at least 33" tires before it'd be satisfactory.. 35" and 5.29 is right around my current gear ratio so it seems decent enough for the tire size. Thanks for the link, Eric
The chart shows that my 4Runner would be running at around 3727 rpm's, which is way too high in my opinion. I only run the engine that high when I really need to get going, so I'd need to run at least 33" tires before it'd be satisfactory.. 35" and 5.29 is right around my current gear ratio so it seems decent enough for the tire size. Thanks for the link, Eric
02-13-2006 | 10:24 PM
#6
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From: Portland, OR
Stick or auto?
No matter what, I would not run 5.29s with 31" tires even for a little while. Unless you enjoy shifting a lot and never go above 50. Save your money (if possible) and swap it all at once.
No matter what, I would not run 5.29s with 31" tires even for a little while. Unless you enjoy shifting a lot and never go above 50. Save your money (if possible) and swap it all at once.
