Drivetrain Rear end gear swap

V-6Pony

New Member
Dec 10, 2019
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Keene NH
2000 V-6 Automatic convertible want to change gear ratio. Has 3:27 with a 7.5 ( I think its a 7.5 have to take a look) running 17 inch tires. Wanted to go with Yucon 3:73 but a mechanic recommended 4:11 any opinions. Not a daily driver just for fun and shows. Not sure what it will do to my MPG, but should give me more speed out of the gate.
Thanks
 
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It seems to me that IF you have any concerns about MPG's, then 4.11's are not for you. Stick with the factory ratios.

I also believe that 4.11's are too low for an automatic. It will reduce the life of the automatic transmission.

There are many people on the forums that are serious fan boys for the 4.11's. I suspect that most do not take extended trips with their 4.11's.
 
Thanks for the reply. Not really concerned about MPG. Car is not really a daily driver. Just weekend trips and car shows. Why you think it will reduce the life of the transmission? Car only was 64K on it. Will at least go with 3.73 for a little more low end get up and go
 
my .02 here...... Before you do this, look into what it will cost you to swap to the 8.8 rear with LSD. In my case I have a 95 vert with a 5 speed. Came with 2.73:1 in a 7.5. I found an 2004 gt 8.8 which had 3.27:1 inside with LSD for $250
 
Why you think it will reduce the life of the transmission?
The 4R70W is a PCM controlled transmission. The programmed shift points are based upon how long it take the transmission to actually change gears and at what RPM the gear change should be completed. When too low of a gear is used this causes the RPM's to rise faster than stock. The net effect is it still takes the transmission the same amount of time to change gears. However the RPM's have risen more/faster due to the lower gear. For this reason it's sometimes necessary to adjust the shift points so that the gear changes have completed at the same RPM.

Also look up "critical speeds" with how it relates to U joints.
 
The 4R70W is a PCM controlled transmission. The programmed shift points are based upon how long it take the transmission to actually change gears and at what RPM the gear change should be completed. When too low of a gear is used this causes the RPM's to rise faster than stock. The net effect is it still takes the transmission the same amount of time to change gears. However the RPM's have risen more/faster due to the lower gear. For this reason it's sometimes necessary to adjust the shift points so that the gear changes have completed at the same RPM.

Also look up "critical speeds" with how it relates to U joints.
Thanks for that information. I will run it by my mechanic and see what he thinks. Going to go with 373's I think the 411's are to much for that car and how I am going to drive it.
 
4.10s... 4.11s are a chevy gear.


Get the 4.10s, people swap to 4.10s all the time with no ill effects. Its one of the best mods to do for an auto to get it off the line quicker. Reduce the life of the trans... lol no. As long as the trans cooler is doing its job it'll be fine.

I also would just find a 8.8 with 4.10s already installed and do the 8.8 swap.
 
2000 V-6 Automatic convertible want to change gear ratio. Has 3:27 with a 7.5 ( I think its a 7.5 have to take a look) running 17 inch tires. Wanted to go with Yucon 3:73 but a mechanic recommended 4:11 any opinions. Not a daily driver just for fun and shows. Not sure what it will do to my MPG, but should give me more speed out of the gate.
Thanks
I'd go with the 4:10 gear. You shouldnt be worried about MPG with a "play" car.
 
my .02 here...... Before you do this, look into what it will cost you to swap to the 8.8 rear with LSD. In my case I have a 95 vert with a 5 speed. Came with 2.73:1 in a 7.5. I found an 2004 gt 8.8 which had 3.27:1 inside with LSD for $250
I’m still wondering how your car with LSD is doing. Did the psychedelic paint job turn out like a flip paint or a 60’s VW bus? :jester:(There’s a reason the term Posi is borrowed from GM.)
I'd go with the 4:10 gear. You shouldnt be worried about MPG with a "play" car.
You have reactivated a Zombie thread.:drool::ack: The threads that show up at the bottom or show up in a search should be date checked. Now if you have experience to add for future searchers, maybe it’s a memorial thread.
 
BTW,

Ford has a TSB for the 99-04 V6 Mustang due to vibrations/noises/etc. The fix (if you were under warranty) was to just install an 8.8 axle. So there are definitely a few V6's out there with a "dealer installed" 8.8 axle already under it.

Every once in a while i'll come across a random thread with some V6 owner asking "is this an 8.8" and actually having one. So always check

Yes...old thread I know