• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Rear end install (3rd member)

  • Thread starter Thread starter geostang351
  • Start date Start date Jan 25, 2007

geostang351

Member
Mar 30, 2005
946
0
17
Danb., CT
Jan 25, 2007
#1
  • Jan 25, 2007
  • #1
I am ready to install my new third member 8" rear back into the car. I have a new gasket and have purchased RTV sealant. My question is do I need to use sealant? Should I use only sealant or if I use both, where do I put the sealant in relation to the gasket, housing and third member?

:SNSign:
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Jan 25, 2007
#2
  • Jan 25, 2007
  • #2
Sealant is optional in this case.

If you think you might need to take it back apart in the next couple of years, I'd skip the sealant as it's a pain to clean off.

Otherwise, it can't hurt. Apply a thin film to both sides of the gasket and make sure the mating surfaces are clean and free of any oil residue.
 
T

truck90278

New Member
Jun 4, 2006
382
1
0
Redondo Beach, CA
Jan 25, 2007
#3
  • Jan 25, 2007
  • #3
Also apply a small amount around the studs
 

geostang351

Member
Mar 30, 2005
946
0
17
Danb., CT
Jan 25, 2007
#4
  • Jan 25, 2007
  • #4
Thank you!!!
 

tos

Founding Member
Apr 27, 2001
896
68
59
Cincinnati Ohio
Jan 26, 2007
#5
  • Jan 26, 2007
  • #5
I think it depends on if the rear-end is out of the car or you are laying underneath trying to install it. I'd use the sealant only if it was out of the car. If the rear-end is still mounted you'll have to wrestle with it a little to get it back in and your RTV will start to setup beafore you get itstalled and tightened down (unless its non hardening RTV.

P.S. I just saturate my gasket with bearing grease. This impregnates the gasket and seals real well. This is also good if you have to pull it back apart next week because something went wrong with the rebuild or your diff makes weird noises.
 

geostang351

Member
Mar 30, 2005
946
0
17
Danb., CT
Jan 26, 2007
#6
  • Jan 26, 2007
  • #6
The rear is in the car and on stands, so I have about 16" of room. I do not plan on taking it out so hopefully all is good.

But you don't give an opinion either way. You actually made the decision a little harder.
 

tos

Founding Member
Apr 27, 2001
896
68
59
Cincinnati Ohio
Jan 26, 2007
#7
  • Jan 26, 2007
  • #7
I think if you read my post again you will see that I did give you my opinion.
I said I would use sealant only if the rear-end where out of the car. Since You now have stated that it is in the car then my suggestion is NOT to use RTV. You will have some trouble getting you third member back in because its heavy and awkward and sometimes they just wont slide back onto the studs easily.

So at this point I would suggest to not use RTV but instead use grease on both sides of the gasket.

Good Luck
 

geostang351

Member
Mar 30, 2005
946
0
17
Danb., CT
Jan 26, 2007
#8
  • Jan 26, 2007
  • #8
Thanks dude!
 
You must log in or register to reply here.

Similar threads

B
water pump installation questions
  • B0udreaux
  • Feb 5, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
38
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Feb 28, 2026
General karthief
Sound deadener install
  • limp
  • Jun 15, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
8
Views
151
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Wednesday at 4:56 PM
limp
A
Help ID - Turbo GT, SVO differences
  • aldoelmalo
  • Jun 2, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
0
Views
56
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 2, 2026
aldoelmalo
A
A
P0036 P0056 P0137 P0157 2020 Ford Mustang GT
  • AmkoA
  • Jun 16, 2026
  • 2024+ (S650) Mustang -General/Talk
Replies
0
Views
44
2024+ (S650) Mustang -General/Talk Jun 16, 2026
AmkoA
A
O
1978 Mustang II Headliner Install
  • onusideburns
  • Nov 4, 2025
  • 1974 - 1978 Mustang II Talk & Tech
Replies
4
Views
347
1974 - 1978 Mustang II Talk & Tech Mar 9, 2026
Enzio
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
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?