• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-

Need urgent help. Timing chain sprocket. VIDEO..

  • Thread starter Thread starter 2003 mustang gt modded
  • Start date Start date Jun 23, 2025

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jun 23, 2025
#1
  • Jun 23, 2025
  • #1
Hi, I have 2003 mustang gt and I'm replacing timing chain and sprokets. How do I untighten timing chain sprocket bolt and how do I torque it. Thanks in advance.
 
Last edited: Jun 23, 2025

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,738
3,187
203
Taylorsville ky
Jun 23, 2025
#2
  • Jun 23, 2025
  • #2
I’m assuming a mod motor, right? If so-how experienced are you ? Do you have the skills set and tools for the job? If No-I’d recommend watching several how to videos on YouTube. If Yes- I’d recommend watching several how to YouTube videos lol
 
Reactions: stormsedge

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jun 25, 2025
#3
  • Jun 25, 2025
  • #3
I did try to search for videos that show how to change timing chain sprockets and couldn't find any.

I'm pretty good with tools. I was thinking of locking the cam with a special tool. But I think the cam will still spin while torqueing.
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
3,960
2,917
194
Middle of Maine
Jun 25, 2025
#4
  • Jun 25, 2025
  • #4
I think there are "flats" on the camshaft that allows a large wrench (7/8" if memory serves) to hold the camshaft while loosening the cam gear bolt.
If you are just changing the cam sprockets, you will need a special tool to hold the timing chain, and more importantly, the chain tensioner in place.
If the front cover is coming off, then that point is moot.
 

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,738
3,187
203
Taylorsville ky
Jun 25, 2025
#5
  • Jun 25, 2025
  • #5
95 mustang gt 302 said:
I did try to search for videos that show how to change timing chain sprockets and couldn't find any.

I'm pretty good with tools. I was thinking of locking the cam with a special tool. But I think the cam will still spin while torqueing.
Click to expand...
I typed in “2003 mustang gt timing chain replacement” these are the first 3 that popped up. The last set I did you use a set of flat bars to lock the cams



View: https://youtu.be/rqsWUZjDtnY?si=NMODPONxnSibyhtu



View: https://youtu.be/sQPaU1cEWVs?si=D1a8Lp8vaBaWrelP



View: https://youtu.be/bMTtatIrkiw?si=FIaQS_74TksHh8lk
 

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jul 8, 2025
#6
  • Jul 8, 2025
  • #6
I appreciate your support guys, and thoughts of just keeping old sprockets in place? 120k miles on them. Keem them or replace them?
 

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jul 18, 2025
#7
  • Jul 18, 2025
  • #7
View: https://youtu.be/RyX2LZ6MfSE?si=1ePme5m3m_TWpYxL
 

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jul 18, 2025
#8
  • Jul 18, 2025
  • #8
The crank timing sprocket mark isn't perfectly centered as shown in video. Pls let me know what you think?

Here is what I did.
1. I set the pulley at tdc.
2.Then took of timing cover, and dots on cam sprockets were facing down, so I turned the engine until they were facing up.
3. Verified the no.1 piston was at tdc. Locked the cams, and installed new chains and verified chain marks and sprocket dots.
 
Last edited: Jul 18, 2025

squeak93

15 Year Member
Jun 2, 2005
2,269
367
164
Joplin, Missouri
Jul 19, 2025
#9
  • Jul 19, 2025
  • #9
Zero reason to replace the sprocket with just 120k unless there is obvious damage/wear or you are putting on new camshafts and don't want to take the factory ones off of the stock cams.

That being said, there are flat spots on the factor cams to "hold" in place while you torque if you chose to do so. New bolts are needed as those are TTY and not reuseable.
 

2003 mustang gt modded

Active Member
Sep 11, 2023
121
13
28
Florida
Jul 21, 2025
#10
  • Jul 21, 2025
  • #10
I did keep old sprokets as suggested by another mustang owner but now I want to double check everything is done right.

I read a thread where someone bent his valves because something he did wrong.

I didn't how you can bend valves when timing chain marks and sprocket marks all line up. Theriadicaly it's impossible unless chain links aren't the same as a defect from factory Assembly.

Anyways I plan to rotate crank bunch of times, use crank positioning tool and check carefully that top sprockets align as same orientation. Having no possibly of valve damage.
 
You must log in or register to reply here.

Similar threads

H
Aluminum timing chain guides ?
  • healy1963
  • May 5, 2026
  • 2005 - 2014 S-197 Mustang -General/Talk-
Replies
0
Views
88
2005 - 2014 S-197 Mustang -General/Talk- May 5, 2026
healy1963
H
S
Timing chain tensioner? (youtube video link)
  • slxne5.0
  • Sep 7, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
130
1996 - 2004 SN95 Mustang -General/Talk- Sep 7, 2025
slxne5.0
S
S
Timing chain, guides and tensioner installation (Possible orientation in Intake Stroke)
  • StallionMax
  • Sep 21, 2025
  • SN95 4.6L Mustang Tech
Replies
2
Views
382
SN95 4.6L Mustang Tech Sep 24, 2025
StallionMax
S
Strange issue with timing Fixed
  • 2003 mustang gt modded
  • Oct 29, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
7
Views
334
1996 - 2004 SN95 Mustang -General/Talk- Dec 4, 2025
2003 mustang gt modded
A
Engine 04 GT timing chain issue
  • AwesomeX1103
  • Sep 3, 2025
  • SN95 4.6L Mustang Tech
Replies
3
Views
377
SN95 4.6L Mustang Tech Nov 5, 2025
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?