Always wanted a 4.10 rear end in the 3.0 Aerostar for more get off the line umph. Just bought new tires 215-75-14. Should have bought 215-60-14 as it would have effectively made it the same as if I had a 4.00 rear end vs the 3.73 it has. Actually the 75 profile tires move it to 3.60. It would have been a blast having more get out in this van, but OTOH the speedo would read 70 mph but would actually be going only 65. Would have to recalibarate, but don't know how. Also the 60 series would lower van about an inch and that would be helpful to stability and cornering, it would seem.
Well I blew my chance.
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Next time paul.
Enjoy the slight increase in fuel mileage.
I guess the alternative is brake torque.
I wonder if there is an ATF desgned to increase the stall speed of the torque converter? Maybe thinner ATF? Might work with Redline.
I wonder if there is an ATF desgned to increase the stall speed of the torque converter? Maybe thinner ATF? Might work with Redline.
Why didn't you buy the 215-60s?
You messed up. Bad. I can't wait for you to tell your mother. Today is the first day of the rest of your life.
Thought of it after the fact. Just as well I guess. Not my van. Wife's van and she would not want the 60s because she does not want the van to ride lower. Probably would not be too happy about the off speedo either. Also, I can just get under to change the oil with the rocker panel dragging slightly on my chest. If I lower it an inch, probably need to jack it up.
Yeah, the high stall thin ATF might do the trick, if there is such an ATF out there. If not, someone should develop it (Bruce?, Mola?). Meanwhile, have it filled with Redline D4 now, so I guess a little brake torquing would not really hurt.
Yeah, the high stall thin ATF might do the trick, if there is such an ATF out there. If not, someone should develop it (Bruce?, Mola?). Meanwhile, have it filled with Redline D4 now, so I guess a little brake torquing would not really hurt.
Originally Posted By: TallPaul
I guess the alternative is brake torque.
I wonder if there is an ATF desgned to increase the stall speed of the torque converter? Maybe thinner ATF? Might work with Redline.
Dexron VI is readily available and starts around 6.0 CST at 100C, and never goes below 5.5 CST at 100C.
That in mind, ordinary Mercon can easily be sheared to 4.5 CST at 100C.
I guess the alternative is brake torque.
I wonder if there is an ATF desgned to increase the stall speed of the torque converter? Maybe thinner ATF? Might work with Redline.
Dexron VI is readily available and starts around 6.0 CST at 100C, and never goes below 5.5 CST at 100C.
That in mind, ordinary Mercon can easily be sheared to 4.5 CST at 100C.
Your gas mileage may read the same, or even seem to go down. This is because the vehicle speed sensor does not know that larger diameter tires are on there.
So gas mileage may go up, but it can read lower!
So gas mileage may go up, but it can read lower!
Right. I guess the change from 70 (stock) to the 75 is not going to throw it too far off. Also, not sure that stock was right on the nose either. I am thinking the 75 series will read 70 but be going about 72 mph. So 280 miles takes 16 gallons for 17.5 mpg, but really is 284 miles and 17.8 mpg. Well that is a bit of a jump.
As for the drive ratio, if I pretend the van came with 15 inch tires, say 225-75-15, and I just switched to the 215-75-14s, then I am really happy at the improved performance which would be the same as keeping the 15s and changing to a 4.00 rear end. It's all a matter of perspective, no?
As for the drive ratio, if I pretend the van came with 15 inch tires, say 225-75-15, and I just switched to the 215-75-14s, then I am really happy at the improved performance which would be the same as keeping the 15s and changing to a 4.00 rear end. It's all a matter of perspective, no?
Well after the 12-inch snow two Fridays ago, I am happy to have the taller tires. Still would love the lower rear gear for good launch.
Originally Posted By: TallPaul
Well after the 12-inch snow two Fridays ago, I am happy to have the taller tires. Still would love the lower rear gear for good launch.
So you can take those Geo Metros stoplight to stoplight?
Well after the 12-inch snow two Fridays ago, I am happy to have the taller tires. Still would love the lower rear gear for good launch.
So you can take those Geo Metros stoplight to stoplight?
Originally Posted By: TallPaul
Always wanted a 4.10 rear end in the 3.0 Aerostar for more get off the line umph. Just bought new tires 215-75-14. Should have bought 215-60-14 as it would have effectively made it the same as if I had a 4.00 rear end vs the 3.73 it has. Actually the 75 profile tires move it to 3.60. It would have been a blast having more get out in this van, but OTOH the speedo would read 70 mph but would actually be going only 65. Would have to recalibarate, but don't know how. Also the 60 series would lower van about an inch and that would be helpful to stability and cornering, it would seem.
My Aerostar sits low enough to the ground with the stock OEM size tires. I wouldn't want it any lower. I think you did good with the tires you went with. Besides I wouldn't want to try and explain to my wife that the Speedo is no longer accurate and how she should compensate for it. Somethings in life are just not worth it!
Frank D
Always wanted a 4.10 rear end in the 3.0 Aerostar for more get off the line umph. Just bought new tires 215-75-14. Should have bought 215-60-14 as it would have effectively made it the same as if I had a 4.00 rear end vs the 3.73 it has. Actually the 75 profile tires move it to 3.60. It would have been a blast having more get out in this van, but OTOH the speedo would read 70 mph but would actually be going only 65. Would have to recalibarate, but don't know how. Also the 60 series would lower van about an inch and that would be helpful to stability and cornering, it would seem.
My Aerostar sits low enough to the ground with the stock OEM size tires. I wouldn't want it any lower. I think you did good with the tires you went with. Besides I wouldn't want to try and explain to my wife that the Speedo is no longer accurate and how she should compensate for it. Somethings in life are just not worth it!
Frank D
Paul
We went from a 99 Tahoe with 3.73 to an 04 Tahoe with 4.10. Trust me you do not want the 4.XX rear----mileage average is 2 mpg less with the 04 on highway and city. In fact when I was breaking in the 04, the computer indicated 8.8 ave mpg
Steve
We went from a 99 Tahoe with 3.73 to an 04 Tahoe with 4.10. Trust me you do not want the 4.XX rear----mileage average is 2 mpg less with the 04 on highway and city. In fact when I was breaking in the 04, the computer indicated 8.8 ave mpg
Steve
Yeah, fuel mileage already is pretty shabby around 16 mpg I think. Also, don't want to mess with wife's van too much. May never hear the end of it if I do, women's memory being what it is.
Originally Posted By: steve20
Paul
We went from a 99 Tahoe with 3.73 to an 04 Tahoe with 4.10. Trust me you do not want the 4.XX rear----mileage average is 2 mpg less with the 04 on highway and city. In fact when I was breaking in the 04, the computer indicated 8.8 ave mpg
Steve
Did you do this by choice.... or did you not know what the gearing meant until after you noticed the fuel economy problem?
Paul
We went from a 99 Tahoe with 3.73 to an 04 Tahoe with 4.10. Trust me you do not want the 4.XX rear----mileage average is 2 mpg less with the 04 on highway and city. In fact when I was breaking in the 04, the computer indicated 8.8 ave mpg
Steve
Did you do this by choice.... or did you not know what the gearing meant until after you noticed the fuel economy problem?
Are you thinking of taking it to Milan Dragway or something ??
Or maybe to Sibley and Dix.
(the good old days)
Or maybe to Sibley and Dix.
Originally Posted By: Drew99GT
Originally Posted By: TallPaul
Well after the 12-inch snow two Fridays ago, I am happy to have the taller tires. Still would love the lower rear gear for good launch.
So you can take those Geo Metros stoplight to stoplight?
Exactly!
Originally Posted By: TallPaul
Well after the 12-inch snow two Fridays ago, I am happy to have the taller tires. Still would love the lower rear gear for good launch.
So you can take those Geo Metros stoplight to stoplight?
Exactly!
Originally Posted By: Papa Bear
Or maybe to Sibley and Dix.
(the good old days)
Ah those were the days. Very sad that drag strip is gone.
Or maybe to Sibley and Dix.
Ah those were the days. Very sad that drag strip is gone.
Better Ice and snow traction with the 21575R14 tires.
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