2000GT4.6

I downloaded JDs GPS vid and noticed something odd. I decided to take the GT to work today and confirmed what I thought.

I have 3.73s in my car, and your RPM@70 MPH is EXACTLY what mine is at 70 mph. Something isnt right here.

Here is what I do know: I had my 3.73s installed by a Ford dealer (stupid me) and I looked on the leftover stuff they gave me and everything said 3.73s. (The part box with my old gears in it did, and some plastic bags) Then, I had my rearend fixed by my performance shop after it started giving me trouble (the Dealer screwed up my install).

I paid jack to get the rear rebuilt, and I didnt have em put in new gears. I can see no reason why they would put in new gears and not charge me, let alone change the ratio without saying so. Also, I noticed no difference when I got my car back. A few months later I had the same shop retune my car and install the cams. My retune sheet says the car has 3.73s. (aka the computer is tuned to 3.73)

I cannot figure out what is going on here. From everything I have heard you have 4.10s. Also, I know that my speedo is exactly on, because it exactly matches my g/fs 2002 Sierra. (driving down the highway with cruise on side by side) The likelyhood of our two speedos being off exactly the same amount is dammed near impossible at best.

So somebody figure this out. WTF is going on???

BTW, I am tacking just like you at 70, right around 2750-2800. My tires are the stock size nitto d/rs, somewhat worn, and my rims are stock.

jdaniel

Well... when im at 70 mph its sitting at 2475 or just barely touching 2500 rpms. When I do 75 mph then im tacking at 2550 give or take. Do you have a 5 speed or an auto?

AWWW!!! You have a 2000. Your 5th gear ratio is lower than mine. They changed that in late 2001 I believe if not later. I still dont think your 3.73's would buzz that high of an rpm at 70 mph though. Sounds more less like you havve 4.30's or something. 70 mph @ 2800 rpms is in 5th gear.... right?

Acer2428

Holy Crap. Even I'm not at 2800rpms at 70mph and I have 4.30's in my auto...

jdaniel

LOL Maybe the tach is off then. HAve you done a digital read out to see if everything is correct? Here is a link that will help you out if you dont know how to do it.

http://www.mustangworld.com/ourpics/fcar/dtcodes.htm

mdvaldosta

YOU GUYS HAVE DIFFERENT FOOKING TRANSMISSIONS!

glad I could be of help.



oops just realized JD said that already... ummm anyways 4.10's on a 3650 tranny in 5th is more like 2400 rpms or so @ 70... you would be about the same as JD in 5th with you having 3.73's and him having 4.10's.... but no way up that high around 2700

GT1999

well im at 75 mph around 2550 2600 rpm and i have a 99 ... and i have the same t45 that 2000 does... but im taching around the same as JD and i have 410s... is that weird?


im at 65 mph around the 2k rpm area and 75 around the 2.5k area w/ 410s and i have the t45... JD has the newer tremec and hes taching the same thing as me... so i assume that the tranny isnt that much of a diff

GT1999

i also have my tires changed to 255/40/17 but i didnt know how to fix that on the predator so i just left it... i wonder if that makes a diff...

2000GT4.6

Bah I wasn't thinking correctly when I posted the number. As I said it was exactly like his, somewhere around 2350-2400. For some reason I was thinking it was just under 3000 RPM instead of 2500.

No wonder I cannot figure out why you guys all like 4.10s, I would be tacking like crazy with 4.10s compared to a 3550 car.

GT1999, today if you can find out exactly what you are taching at 70 MPH.

jdaniel

No trust in me I see. LOL

GT1999

woops , sorry, im at 70 at 2500 and 65 and 2000 RPM... not 65 and 75... lol