2003-04 Mach 1 Registry Owners Club  


Go Back   2003-04 Mach 1 Registry Owners Club > "GO" Discussions > Engine & Drivetrain (Including trans & rear axles)

Reply
 
Thread Tools Display Modes
Old 01-20-2021, 12:16 AM   #26
Twitch
Registered User
 
Twitch's Avatar
 
Join Date: Apr 2019
Location: college station
Posts: 17
Re: Need Some Rearend help/info

Quote:
Originally Posted by ASH302 View Post
I am blown away with this information about the stock mach diff. Just blows me away and why Ford would not have replacement parts or anyone just blows me away.
My rear end isn't stock so i'm not worried about it, but feel bad for you and others out there with the stock diff.

ASh
My cousin says that this is starting to become more of the norm for car manufacturers. They say its cheaper or about the same price to replace the entire diff unit than to rebuild after you count all parts and labor so in the end its just easier.

I can kind of see the point but for some that just need a specific part to get things back in order, that ends up not being true for DIY'er.

Guess If im going to replace the diff then I'll just upgrade the rear to a 31 spline mainly cause aftermarket parts are more plentiful for the 31 spline 8.8 after all my research.

I dont get why Ford went kinda weird on the Mach. Couple yrs back I couldnt get an alternator anywhere. Ford dealer,Napa, and another place ordered me a new one and it would not fit, none had the shaker mount holes on them. All ford did was get a Cobra one, didnt work,holes didnt line up. Just had original rebuilt nearby been good since.
Twitch is offline   Reply With Quote
Old 01-20-2021, 02:27 AM   #27
ASH302
Soldier for Christ
 
ASH302's Avatar
 
Join Date: May 2009
Location: Willis, TX at The Daddy ASh Ranch
Posts: 30,476
Re: Need Some Rearend help/info

yea that is crazy.
Honestly if you can swing it get the built one.
on my 04 I did the Cobra diff and 31 spline, but kept stock gears.

my 03 came with the rear built with 4.10s, it is a whole other animal on the street.

ASh
__________________
2001 lazer red v6 Mustang coupe sold in Aug 2006
2004 screaming yellow 5.0 sc Mach 1 sold in Oct 2012
2013 grey 6 speed coupe GT Mustang Sold in Feb 2014
2013 RED Dodge Charger R/T Sold Nov 2014
2002 custom Blue 02 Auto Trans AM Sold June 2015
1998 Cobra Black Sold summer 2016

Current
2009 Ford F350 FX4 March 2017 (work truck)
2003 OW 5.0 Mach 1 Aug 2020

ASh
ASH302 is offline   Reply With Quote
Old 01-20-2021, 03:44 AM   #28
Twitch
Registered User
 
Twitch's Avatar
 
Join Date: Apr 2019
Location: college station
Posts: 17
Re: Need Some Rearend help/info

Quote:
Originally Posted by ASH302 View Post
yea that is crazy.
Honestly if you can swing it get the built one.
on my 04 I did the Cobra diff and 31 spline, but kept stock gears.

my 03 came with the rear built with 4.10s, it is a whole other animal on the street.

ASh
Yea mine came with stock diff. But took the car into local ford for a warranty repair. They said rear diff bearings were bad which I highly doubted but figured hey, new bearings installed for free.
Get car back and 2 months later bad sounds in rear, ford said whoever I had do work on the rear installed it wrong and it somehow trashed the whole rear....lol.

I told them they did the work...lol.
But get this. I get the car back after the new rear was done,kept driving around and getting passed by everyone. My speedo was 10 mph off.
Told Ford they put wrong gears in, fix my speedo.

They wouldnt without proof but wanted to charge me $100 to open rearend and look...NOPE. Showed them proof that they somehow installed 4.10's..

So free 4.10's and then they paid for the FRPP Speed-Cal box...lol

Same Ford dealer that ruined 2 engines in my dads truck over a 2 week period, no joke. 1st motor they left a tool somewhere between the tranny and motor and it knocked a hole in the block.Week later a new motor and they cracked the block near the head. So motor 3 was the charm...lol
Twitch is offline   Reply With Quote
Old 01-20-2021, 11:11 AM   #29
ASH302
Soldier for Christ
 
ASH302's Avatar
 
Join Date: May 2009
Location: Willis, TX at The Daddy ASh Ranch
Posts: 30,476
Re: Need Some Rearend help/info

I think I would try a different Ford dealership, lol.
I'm in Willis and a big Ford dealership a few exits up, I will not use them for service type stuff. I drive all the way to Huntsville to have all work done.
4.10s are fun, but not, depends which way i'm driving. I think I would like 3.73.
For sure don't like 4.10s on the hwy while cruising.

ASh
__________________
2001 lazer red v6 Mustang coupe sold in Aug 2006
2004 screaming yellow 5.0 sc Mach 1 sold in Oct 2012
2013 grey 6 speed coupe GT Mustang Sold in Feb 2014
2013 RED Dodge Charger R/T Sold Nov 2014
2002 custom Blue 02 Auto Trans AM Sold June 2015
1998 Cobra Black Sold summer 2016

Current
2009 Ford F350 FX4 March 2017 (work truck)
2003 OW 5.0 Mach 1 Aug 2020

ASh
ASH302 is offline   Reply With Quote
Old 01-20-2021, 01:43 PM   #30
Twitch
Registered User
 
Twitch's Avatar
 
Join Date: Apr 2019
Location: college station
Posts: 17
Re: Need Some Rearend help/info

Yeah I dont use them. I only did yrs back just cause of the warranty I got with the car.
Believe or not thats just the worst stuff they have done. Dad took same truck in that they blew the motors to get oil change and tire rotation, he got about half mile down the road and rear wheel fell off.
After that he got rid of the truck, figured it was a sign...lol

As for the 4.10's,when I do the diff I may drop down to 3.73's. 4.10's are fun but my gas mileage took a beating. With the 3.55's I drove to Dallas and back and averaged about 27mpg, now its more like 22 and a lot of changing gears.
Twitch is offline   Reply With Quote
Old 01-20-2021, 02:12 PM   #31
DSG2003Mach1
700 HP Mach
 
DSG2003Mach1's Avatar
 
Join Date: Nov 2003
Location: Orlando, FL
Posts: 8,332
Re: Need Some Rearend help/info

Quote:
Originally Posted by Twitch View Post
The same here, I couldnt believe Ford did that. I would have at least thought an aftermarket company would have had something but no luck and if there is no one knows what part number it is to even try ordering.

It just sucks I have to buy the entire carrier setup since the diff has new bearings and seals, thats how I found out about the 2 chipped teeth on the spider gear. But since I cant find any part for it I put it back together for time being and thats been 2 months ago now....lol.

Its really not bad, I cant tell by driving it,makes no noise,no whine or popping at all. Backlash is in spec.

Is the trutrac a noisy rear?
Ive heard that you can hear the posi engage if I remember correct about the one I was reading about.
I have a procharger with a BRRV and full exhaust, if it makes noises its not enough to hear over all that. I do have a bit of a thumping sound on decel sometimes but thats about it
__________________
03 dsg mach1 - MPR built 9.5:1 motor, D1, cams, ported intake, full exhaust, magnum t56, built rear, E85 etc...

'12 F150 FX2 Supercrew with Ecoboost daily beater
DSG2003Mach1 is offline   Reply With Quote
Old 01-20-2021, 03:07 PM   #32
Twitch
Registered User
 
Twitch's Avatar
 
Join Date: Apr 2019
Location: college station
Posts: 17
Re: Need Some Rearend help/info

Quote:
Originally Posted by DSG2003Mach1 View Post
I have a procharger with a BRRV and full exhaust, if it makes noises its not enough to hear over all that. I do have a bit of a thumping sound on decel sometimes but thats about it
Thanks for the info.
Prob gonna do the whole diff change out/upgrade next month. Got a good deal on a set of FR500 9" wheels and 275 tires from AM I couldnt pass up, just under $1000 mounted and shipped. Calling them is much cheaper than just online order, always get better deals. Discount tire quoted me $1500 for the exact same setup.

Hopefully the diff dont go boom in the meantime...lol. Doubt it,like I said I wouldnt have even known if I wasnt in there doing carrier/axle bearings and seals. Its just knowing couple chipped spider teeth bugs me.
Twitch is offline   Reply With Quote
Old 01-20-2021, 03:11 PM   #33
Twitch
Registered User
 
Twitch's Avatar
 
Join Date: Apr 2019
Location: college station
Posts: 17
Re: Need Some Rearend help/info

Finally figured out the profile avatar,lol kept telling me upload failed.
Twitch is offline   Reply With Quote
Old 01-20-2021, 07:14 PM   #34
ASH302
Soldier for Christ
 
ASH302's Avatar
 
Join Date: May 2009
Location: Willis, TX at The Daddy ASh Ranch
Posts: 30,476
Re: Need Some Rearend help/info

Quote:
Originally Posted by Twitch View Post
Finally figured out the profile avatar,lol kept telling me upload failed.
LOL,

ASh
__________________
2001 lazer red v6 Mustang coupe sold in Aug 2006
2004 screaming yellow 5.0 sc Mach 1 sold in Oct 2012
2013 grey 6 speed coupe GT Mustang Sold in Feb 2014
2013 RED Dodge Charger R/T Sold Nov 2014
2002 custom Blue 02 Auto Trans AM Sold June 2015
1998 Cobra Black Sold summer 2016

Current
2009 Ford F350 FX4 March 2017 (work truck)
2003 OW 5.0 Mach 1 Aug 2020

ASh
ASH302 is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:28 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
(c) 2002-2013 Mach1Registry.com

<