hellish vibration

Crone · Apr 8, 2010

I put a rear in the car a few weeks ago with 4.10s. I didn't get the speedometer gear yet so I don't know the actual speed it starts at but when the speedo reads 110 it would vibrate the entire car, we checked everything, found that the left wheel bearing in the rear was bad so we replaced it. now it doesn't vibrate until 120. It does it wether i am on the gas or not, and even in neutral. any ideas??

JDwhite98gt · Apr 9, 2010

I dont think its shimmed correctly. I have the same problem but its off the gas in neutral or in gear. I've heard that on the gas noise or vibration is too tight, off the gas is too loose....yours just might be out of whack completely. Do you have any noise or whine? Does it sound like a jeep with 37 inch tires?

MustangChris · Apr 9, 2010

id check your u joints and have your driveshaft balanced. easy enough.

does it make a whining sound? that would lean towards a bad-install on the gears.

Also, (with my personal experience) they dont make a 4.10 speedo gear... 3.55 is the highest speedo gear i could find and it was from steeda. speedo is still off, but slightly closer.

are tehre any other problems? does it vibrate in a rythmatic fashion? or just at a certain speed? or all the time?

jojo22 · Apr 9, 2010

Chris, call the stealership, I called and they told me they had the speedo gear for 4.10 gears

jojo22 · Apr 9, 2010

Or you could just hit this link and order one!!

http://www.steeda.com/products/speedometer_recalibration_gears.php

MustangChris · Apr 9, 2010

jojo22 said:
Or you could just hit this link and order one!!

http://www.steeda.com/products/speedometer_recalibration_gears.php

i purchased that 4.10 speedo gear...
had it professionally installed...
it didnt work and they said "it was just like the old one, but you told us to install it..."
so i call up steeda, whom i hate with a furry...
"WTF, n00bs?" - I said...
they were like "they are all the same product, take a look at the part number. they are meant for 3.55s, but they are as close as you will find for 4.10s"

part numbers (off link you posted)
392-STE-17271-J - 4.10s
392-STE-17271-J - 3.73s
392-STE-17271-J - 3.55s

so i call my performance dealership here...
"wtf, mates?"

after speaking with the tech guy, who has done mustang crap for 100 years... he told me that after doing the math (he took into account my wheel size, tire size, gear ratios,) i would require a 23 spline gear. and the closest thing he could think of that would work would be a 21(or 22) spline gear out of a crystler.

so, dallas speed cal is still what i suggest to people going 373 or 410s.

jojo22 · Apr 9, 2010

Okay, I just remembered seeing them, and ford telling me that they could get one but I guess not.

Can that be fixed with the tune.

MustangChris · Apr 9, 2010

jojo22 said:
Okay, I just remembered seeing them, and ford telling me that they could get one but I guess not.

Can that be fixed with the tune.

maybe they can now. i dono. lol. this was 2 years ago when i did my rear end build.

but i dont think a speedo on a machanical drive can be fixed with a tune. (1994-1998) i do *believe* a 99+ can be fixed with a tune.

jojo22 · Apr 9, 2010

So are there any other ways to fix the speedo??

MustangChris · Apr 9, 2010

i *think* the speedo is driven by a gear in the cluster as well.... the guy on the ford tech i was talking to said even if you mess with that gear and the transmission gear, you couldnt get an accurate reading.... dallas speed cal is the best bet.

jojo22 · Apr 9, 2010

Okay sorry to whore the thread but it's still on topic.

I googled the dallas speed cal, and steeda had it listed for 99-04 mustangs, how would someone like me (98 GT vert) use this product to correct the speedo?

MustangChris · Apr 9, 2010

here you go amigo ;-)
http://www.americanmuscle.com/speed-calibrator-94-04.html

http://www.americanmuscle.com/speed-cal-install.html

PS: i hate steeda, they can lick my c0ck.

jojo22 · Apr 9, 2010

Thank you, 4.10's are top of the list when I get mine, so that will be a great help!

Crone · Apr 9, 2010

I do have gear whine when I give it gas. Guess I woulda been better off just installing the 3.55's I have in my old rear so it could have been done right. Maybe I'll check into balancing the driveshaft, thanks guys