Brenspeed vs AM employee opinion
 

I have searched high and low on here for people with 4:10s on their auto s197 and most people like them and say they are not bad at all for daily driving. Then I go to the pros and Brenspeed says their perfectly fine, while American Muscle says they are to hard on the tranny for daily driving and recommends 3:73s. SO...again I am not sure. It is my daily driver in the summer to work and for leisure and may see a couple track days at most.

Do you drive on the freeway? 4.10's are fun around the city but when you get to high speeds they're not that fun.

They're not hard on the trans at all.

4.10's in O/D at 70mph will put you just a hair above 2500 rpm. So ~500 higher than stock 3.31.

I have no complaints about my 4.10's. On or off the freeway, they are fine.

You really cant go wrong either way! either one will make a noticeable difference in performance. if your not going to the track on a regular basis,then the 3:73 would probably be fine for you. FWIW..even ford racing suggests the 3:73 for the autos.

I had both 3.73s and now 4.10s in my auto DD. I just drove 1000 miles in the past four days on 4.10s. No problems ever.

Not sure why it would be hard on the tranny. I noticed a slight difference in the way the auto shifts from my first mod (cai and tuner). The shifts with that were much more aggressive compared to how the car shifts now and i have 410's. However When i go to the track which is around 2 to 3 times a year the car pops them in third which seems to me that it redlines and then goes right into gear which im sure is hard on the tranny. First and second feel fine but second to third im guessing is a bit hard on it. With that said if ur tranny broke u could always just upgrade it

The ratio of the gears themselves don't have any impact on how hard the shift is, though. That's all within the tune, which of course you could have lowered (shift harshness) by your tuner.

i have a 5 spd but i herd that 3.73 for an auto is like 4.10s for the manual. i really dont know that. and i dont see how it would hurt the tranny at all

that makes sense. So does anyone know if there is really any wear on the transmission due to a gear swap