Mach 460 and differential problems

mmills421 · 11-26-2003

Yeah, I had an Alpine CVA-1003 put in...it's a pretty nice control system with flip out tv screen..I had a dvd player put under the passenger seat and a cd changer in the trunk. I'm not sure if they bypassed the stock amps...which could be one of the problems...that would mean I have 45 watts coming from the head unit + whatever the stock amps put out...the 2 amps in a line probably wouldn't be a good thing if that's what they did...I'm going to talk to the installer to find out exactley what happened here...

Also...ATOMIC....I have a 96 with 3.73's and they are just about perfect..it's my daily driver and I love the off the line/highway speed ratio...no real noticable noise either..

atomic_stang · 11-26-2003

I think I'm gonna go with the 3.73s.

I'll definitely swap out the head unit in favor of an MP3 player of some sort. Something less than $300.
Any suggestions?

When I do, I'm very reluctant to use the 460 amps. I had the premium sound system in my 94 Navajo and after I installed an MP3 player (Sony CDX-MP40) using the factory amps, there was this constant hiss when I played a CD and the volume was too loud. At the lowest volume level it was too loud to carry on a normal conversation. It was probably cause I used the built in head units amps instead of the pre-amps.

atomic_stang · 11-29-2003

Finally installed my 3.73 ring and pinion today. I had to replace all the bearings because they were all shot. The forward pinion bearing was the worst and my dad tells me it probably failed first and the debris took out the others. Let me tell you if you don't already know, completely rebuilding a differential is a major B***. Not only did I have to press all the bearings off, but I had to replace the races too. Needless to say it was a long, tiring ordeal. I highly discourage newbies from attempting a complete rebuild without hands-on guidance and the correct tools. And a lot of patience. Hopefully most wont have to replace everything like I did which obviously will takes more time than just changing a ring and pinion.

But I must say I'm enjoying the fruits of my labor. The 3.73 ratio does seem to be the ideal gear for my car. I havent really pushed the car yet to see how much better my take off is, but driving response feels a lot more crisp.

But now it seems, I have a +10mph speedometer error. I.E. whenever my car says I'm going 55mph, I'm actualy doing 45mph. I checked it with a GPS. I went to the Ford dealer today and got the gear that should have corrected the error, but when I popped out my speedometer cable there wasn't a speedo gear. It looked like a sensor

. Anyone know what this is and how I calibrate my speedo???

GTron · 11-29-2003

Quote:

Originally posted by atomic_stang

But now it seems, I have a +10mph speedometer error. I.E. whenever my car says I'm going 55mph, I'm actualy doing 45mph. I checked it with a GPS. I went to the Ford dealer today and got the gear that should have corrected the error, but when I popped out my speedometer cable there wasn't a speedo gear. It looked like a sensor . Anyone know what this is and how I calibrate my speedo???

I changed from 2.73 to 3.27 gears in a 98 V-6 Mustang with a 4R70W automatic over drive trans. there was a sensor at the tail shaft with a wire running to the speedometer head. When I unbolted the retainer that held it to the case there was a gear in there that ran off of the tail shaft. Are you sure that there is no gear????

atomic_stang · 11-29-2003

Yeah, there was no gear. I said speedometer cable when actually it was a harness (sorry!). I unplugged it, then used a 10MM wrench to remove the "pickup". My dad has changed speedo gears in lots of T5 transmissions and was surprised at what I showed him. I even asked him to look under my car to make sure I had actually removed the right thing and he confirmed it.

I've done some reading in the forum and it seems that in '99 Ford went exclusively to this type of system. I've read earlier AOD Mustangs ('98?) also used a pickup type system.

From what I've read so far, the only practical way to correct this error is to purchase what is called a "SpeedCal" from Dallas Mustangs and is about $100. Yikes. Whatever happened to an $8 speedo gear change??

Any other solutions to this problem anyone is aware of?

bgt98 · 11-30-2003

For the head units, check kenwood the next couple months....their new stuff always comes out in stores around february of the new year and the stores are always trying to get rid of their last years products. I did this and got a top line kenwood excelon with color mpeg screen, mp3 playable and sirius ready for 320.

Pushing 45/50 watts is fine for factory speakers, with the amps its too much. Theres two adapters that they use to by pass the amps i think around like 100bucks or so. The clarity will be a night and day difference n sound also...fuzzy a** quality in the factory units.