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installing ford 3.55 gears without measureing

  • Thread starter Thread starter dastang2
  • Start date Start date Mar 19, 2006

dastang2

Active Member
Dec 11, 2003
2,020
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46
tx
Mar 19, 2006
#1
  • Mar 19, 2006
  • #1
i heard that since these a ford gears, that you can just pull the old ones out and swap these in without reshimming or taking measurements. is this true. thanks. couldn't i just use bluing or something to show the wear pattern and match it up to the old gears or a book's diagram
 

86mustang5.oh

New Member
Apr 5, 2005
125
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0
battle creek mi.
Mar 19, 2006
#2
  • Mar 19, 2006
  • #2
i did my 3.73s like that just switched them still works
didnt measure annything
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Mar 19, 2006
#3
  • Mar 19, 2006
  • #3
how long have you been running them like this. are they ford gears
 

rd

Founding Member
Jan 12, 2000
3,316
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109
Ocean Springs MS
Mar 19, 2006
#4
  • Mar 19, 2006
  • #4
The Ford Gears seem to have a reputation of being able to do that. I set up one set of 7.5 in gears that way, using the stock pinion shim and they work well. I did measure backlash and have adjusted it twice, down to about .009 or so. This is the SVO 4.10 set in my 82, which I installed with a new SVO traction lock in about 1995.
 

chaos254

Founding Member
Jul 27, 2002
467
3
29
NJ
Mar 19, 2006
#5
  • Mar 19, 2006
  • #5
bump, i'm interested in hearing more responses about this...
 

stang8urimport

Autozone Junkie
Founding Member
Jun 21, 2002
1,499
12
59
Daytona Beach, FL
Mar 19, 2006
#6
  • Mar 19, 2006
  • #6
I have also heard this. A friend of mine has swapped from OEM 2.73s, to FMS 3.55s, to FMS 3.73s, then FMS 4.10s without ever measuring anything and never any gear whine or any problem with the gearsets. I say go for it.
 
D

dec322

Member
Feb 11, 2006
401
2
16
Bham AL
Mar 19, 2006
#7
  • Mar 19, 2006
  • #7
This thread is sending me into a tailspin. I am wanting to get gears installed and have been disappointed in the price of labor ($375). This is to replace the gears (3:55) and install new bearings, seals, shims....... I thought all the extra stuff was necessary in order to do it "right".

I am wrong? What is the point of the new bearings and stuff if all I really want is to start a little quicker with some new gears (I have 2:73)?
 
J

jmd2914

Founding Member
Sep 6, 2002
937
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Napa, California
Mar 19, 2006
#8
  • Mar 19, 2006
  • #8
I'm also very interested in this thread, i have a set of 3.73's out of an expedition that i got from a friend. they just swap right in?
 

stang8urimport

Autozone Junkie
Founding Member
Jun 21, 2002
1,499
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59
Daytona Beach, FL
Mar 19, 2006
#9
  • Mar 19, 2006
  • #9
The bearings and seals are good to replace while you're in there.... To replace those you will need a press and a slide hammer to get the axle bearings out.
 

TheBocSez

New Member
Feb 3, 2004
652
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0
Converse, TX
Mar 19, 2006
#10
  • Mar 19, 2006
  • #10
Thats how I installed my Ford 4.10's. Pulled out the 2.73's keeping the bearing caps and shims together to put back on the same sides. Threw the 4.10s in, they were used and the old pinion bearing was still pressed on the 4.10's threw the stock shims and all back in and was done. No whining or noises and has worked find for about 10000 miles now.
 

MdntRanger50

Member
Jan 21, 2002
32
0
7
Central La.
Mar 20, 2006
#11
  • Mar 20, 2006
  • #11
I did this with a 7.5 one time went from 3:45 to used 4:10 gears without measuring. I did reuse the shims that were in the rearend that the 4:10 gears came out of though. I checked the mesh pattern with some gear marking compound and it looked good so I ran them without any problems.
 

jackchan

New Member
Oct 17, 2004
507
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Mobile Alabama
Mar 20, 2006
#12
  • Mar 20, 2006
  • #12
the key to this is reusing the old pinon shim or one the exact same thickness........and also when doing this use a new crushsleeve with new pinion nut. IF the "crush sleeve" is set correctly you shouldnt have anyproblem......I've set up more than 40 sets of gears without any problems.....no matter the gear. Richmond, Precision gear, Motive gear, FRPP gears....doesnt matter. Again I say, the key is using the same thickness shims behind the pinion bearing.....and set up your drag on your pinion nut "collar" to be between 16 inch lbs to 23 inch lbs of torque. When I say this I mean so when you spin your round collar that your drive shaft bolts to it has 16 to 23 inch lbs of torque to rotate the collar.
one day I'm gonna do an article on this and post it on my website.
Ben
 

302RollinHard

New Member
Sep 26, 2005
0
0
0
Columbus, OH
Mar 20, 2006
#13
  • Mar 20, 2006
  • #13
Just to be the Devil's advocate, while you got all that stuff out of there, make sure to check everything and replace carrier bearings, etc if needed. No point in changing just gears and shorting yourself. I would assume if it is an honest shop if it is charging $375 (with you providing ring & pinion) they would be planning on replacing axle/carrier bearings, perhaps even a rebuild for that price.
 
D

dec322

Member
Feb 11, 2006
401
2
16
Bham AL
Mar 20, 2006
#14
  • Mar 20, 2006
  • #14
302RollinHard said:
Just to be the Devil's advocate, while you got all that stuff out of there, make sure to check everything and replace carrier bearings, etc if needed. No point in changing just gears and shorting yourself. I would assume if it is an honest shop if it is charging $375 (with you providing ring & pinion) they would be planning on replacing axle/carrier bearings, perhaps even a rebuild for that price.
Click to expand...

I don't know alot about this topic. The $375 does replace the axle/carrier bearings and all that stuff. Is that considered a rebuild?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Mar 20, 2006
#15
  • Mar 20, 2006
  • #15
Backlash for a street car and a race car is different....and Fords tolerances are all over the place from what I have seen.

For comparison sake I charge $200 LABOR ONLY to install and set-up new gears, bearings and seals are extra usually around $100 in parts, I'll rebuild the carrier with the extra clutch for another $60 Labor, $40 in parts.
 

rd

Founding Member
Jan 12, 2000
3,316
63
109
Ocean Springs MS
Mar 20, 2006
#16
  • Mar 20, 2006
  • #16
After doing this several times, if possible, I do not change the carrier bearings, etc. If they are in good shape, there's no reason to change them. The pinion bearings are different. The inner has to be pressed off and on, and to get the oem shim, so it is subject to being damaged during that activity. I usually have another one handy just in case.

But lately, I've used it over also.

Bottom, line, if I was starting with a new carrier, I'd probably get new bearings. Otherwise, re-se.

I have also decided not to collect this stuff, so if I can use it, and not just have it stuffed in the garage, that's a plus these days.
 
2

2_fast_4_ya

New Member
Dec 5, 2004
11
0
0
norhtwest ark
Mar 21, 2006
#17
  • Mar 21, 2006
  • #17
i did my ford gears without measuring, just make sure what you take off goes back in the exact same place it came from and you shouldnt have any problems. i have had mine in for a good 30,000 miles.
 
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