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3650 Question

  • Thread starter Thread starter 00stangv6lr
  • Start date Start date Nov 1, 2007

00stangv6lr

New Member
Sep 25, 2006
61
0
0
Omaha, NE
Nov 1, 2007
#1
  • Nov 1, 2007
  • #1
When I first get into my car and drive it around, I get a loud grinding noise when I shift to 2nd gear. This is the only gear its grinds into. After I drive for about 10 miles, the car shifts normal into 2nd. I installed RP Synchromash and a MGW shifter but neither of these helped. I am just wondering if this is normal and if its not how to fix it. Thanks.
 

bullitt 736

Member
Jan 16, 2004
120
0
17
Magnolia, Texas
Nov 2, 2007
#2
  • Nov 2, 2007
  • #2
The 3650 does not use Synchromesh. Mercon/Dexron III is specified. I would get some and replace what you have. I prefer Amsoil. but the choice is yours. Also the 3660 uses 3.2 quarts. Do not overfill.
 

Mustang225

Founding Member
Jul 23, 2000
424
5
29
Nov 2, 2007
#3
  • Nov 2, 2007
  • #3
00stangv6lr said:
When I first get into my car and drive it around, I get a loud grinding noise when I shift to 2nd gear. This is the only gear its grinds into. After I drive for about 10 miles, the car shifts normal into 2nd. I installed RP Synchromash and a MGW shifter but neither of these helped. I am just wondering if this is normal and if its not how to fix it. Thanks.
Click to expand...

Do a search on the 3650 and then get ready to read, read and read.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,268
17,954
224
Massachusetts
Nov 3, 2007
#4
  • Nov 3, 2007
  • #4
Yup....it's a 3650 design flaw


the synchromesh doesn't help either. Get the right fluid back in there
 

Spro

New Member
Nov 3, 2007
73
0
0
IL
Nov 3, 2007
#5
  • Nov 3, 2007
  • #5
Actually the RP synchromax is fine in the 3650. I have it in mine as well and know many people that use it in the 3650. It's not gonna hurt the trans. It's really good fluid. Sounds like you need a rebuild like me.
 

R.J.

Member
Aug 20, 2003
813
0
16
Warwick, Rhode Island
Nov 4, 2007
#6
  • Nov 4, 2007
  • #6
+1 syncromesh
I called Tremec and got the answer about fluid type and usage right from the horses mouth. They reccomend (in order) 1. conventional Mercon/Dexron III (no specific brand) 2. Mobil 1 3. Syncromesh (when your tremec becomes noisey)
You can call them yourself, I don't see why they would give you any different answer. just my .02
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,268
17,954
224
Massachusetts
Nov 4, 2007
#7
  • Nov 4, 2007
  • #7
R.J. said:
+You can call them yourself, I don't see why they would give you any different answer. just my .02
Click to expand...


They have given me a different answer.


I was told by a tremec engineer that the synchromesh reacts with the materials in the blocker rings linings in pretty much all their transmissions except the 3550 series in which that fluid is recommended.

That was a few years back though, so unsure if they've changed their song. never was concerned much to do much reading into it.

Still though, i 'll stick to ATF even though i know a lot of people run synchromesh no problem
 

blckstng96

Member
Apr 13, 2004
208
0
16
Nov 5, 2007
#8
  • Nov 5, 2007
  • #8
i dont think the fluid is going to help,maybe but prob need a rebuild
 

smokin91'

New Member
Feb 19, 2006
204
2
0
Nov 6, 2007
#9
  • Nov 6, 2007
  • #9
you guys are getting the 2 confused.

SYNCHROMAX - made by royal purple is a manual transmission fluid made for transmissions that call for ATF.


SYNCHROMESH - Is the General Motors product which some people have said tremec has told them will eat the coating on the synchros over time and is not recommended for the 3650. Some guys on here are still running this in their 3650 and say it works fine.


BTW you will never get a definitive answer on this subject, and as far as ford is concerned they consider this normal transmission operation. Enjoy your 1-2 grind!

Tell me this tho, once its warmed up, does it not shift PERFECT.. like once ive driven for 5 mins, it becomes the smoothest transmission ever, however when its cold, it does the 1-2 grinder.
 

smokin91'

New Member
Feb 19, 2006
204
2
0
Nov 7, 2007
#10
  • Nov 7, 2007
  • #10
My car is having an overnight sleep at ford so they can take it for a ride in the morning when its cold. This is the 3rd time now. Both times previous I got the we cant replicate the problem. Its supposed to be below freezing tomorrow morning I guarantee it will do it like crazy. Its been doing it for me everyday for the past month since I took it in the last time.

If they tell me they cant duplicate the problem, I dont know what im going to do.
 

00stangv6lr

New Member
Sep 25, 2006
61
0
0
Omaha, NE
Nov 7, 2007
#11
  • Nov 7, 2007
  • #11
Yah thats exactly what it does. It shifts perfect after its warmed up. I think I said Synchromesh, but I meant synchromax by Royal Purple. And Syncromax is perfectly fine for the 3650.
 
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