4.10 gears = 200,000 miles ?

[michaelleewebb]

i'm reading from the beginning of this forum till today, back in 2003-2004 people were saying that the best mod to do was change the gears to 4.10. i think thats a really bad idea. i'm mean whats the engine rpm at 80 mph ? 3500 rpm ? i was wondering after all these years if anyone has a mustang with 4.10 gears that made it to 200,000 miles.

i would think the best mod for the car would be a 6 or 8 speed automatic. has anyone ever done that ? i haven't read thru all the forum yet, i'm on page 196.

 

[KRUISR]

Here's my 2 cents...

4.10 gears - at 80 mph with a T5 (overdrive 0.68), RPM would be 2950 with stock height tires. Not crazy RPM, but could get annoying over a few hour drive. Personally I would do a long highway run at no higher than 70-75 mph which would be 2500-2700 RPM. Drive 200,000 miles with 4.10s, most folks that put 4.10s in are not using the car as a long distance commuter. They may drive it often, but likely not 15,000 miles per year, probably 1-2000 per year max. So that would take 100-200 years to achieve that many miles with 4.10s installed.

6 or 8 speed conversion. Likely would not help much (if any). Look at the ratio of the highest gear. Rarely much lower than at T5 (I know a TR3650 has a 0.62 5th gear). For example, a 6R80 (very common for use with Coyote swap) has a 0.87 5th gear and a 0.69 6th gear, so slightly worse than a T5. The Ford 10spd has a 0.854 8th gear, 0.689 9th gear and a 0.636 10th gear (very slightly better than a T5).

Where the 6 or 10 speed conversion helps is due to the higher first gear you can run a lower rear gear (stock are typically 3.31s) which gives the lower RPM on the highway and still plenty of overall ratio at the start.

 

[michaelleewebb]

it doesn't look like their are any 6 speeds out there that would fit the 3.8 engine anyway. at least not without crazy mods. i think alot of people who bought the 3.8 and only plan to drive it 2000 miles per year would have been better off getting the v8. still i would like to know if anyone made it to 200,000. guess i'll have to wait till 2150 or so.

 

[KRUISR]

You didn't mention you were talking a V6. I assumed you had or were talking about a V8. If you are looking to make your V6 a little snappier off the line, sure go with 4.10s, they will work fine and help alot.

 

[Mustang5L5]

still i would like to know if anyone made it to 200,000.

There are a lot of Mustangs out there that have made it to 200K miles or more. I have about 100K on mine with 3.73's (installed in 2001) and I would almost be certain there are guys out there with more than that on 4.10's.

What exactly is your concern? Pure RPM's is one part of the equation when you are trying to determine cycle time and lifespan, but load is also another factor. Yes, you are putting more RPM's through your driveline, but you are also reducing load when cruising.

What component are you most worried about wear and tear on? Transmission?

 

[michaelleewebb]

the engine. i don't remember right now what my stock 3.8 engine (with stock rear end) spins at 80 mph. but it's got to be alot less than 4.10 gears. i would think that the piston rings would wear out faster. just from going up and down that many revolutions more. i question if anyone has made it 200,000 miles with 4.10 gears, also i mean with the 3.8 liter engine. my understanding is that people that have 4.10 gears don't do alot of highway miles. also i have no intention of installing 4.10 gears in my old car. i'm losing oil pressure when its idling and warmed up. i fear my horse is on its last miles. i forget how many miles it has now, something like 220,000 or 214,000. i've been good to her and she has been good to me. when she dies i'll get another pony. perhaps a slightly newer model.