Notices

944 Transmission Walkthrough (image heavy)

 
Old 03-20-2012, 07:25 AM
  #1  
JET951
Addict
Rennlist Member
Thread Starter
 
JET951's Avatar
 
Join Date: Nov 2005
Location: Sydney Australia
Posts: 2,513
Default 944 Transmission Walkthrough (image heavy)

Well i have been meaning to put this together for some time. Here is a general walk through of our 944 Transmissions. This one in Particular is a 944 turbo trans, We are setting it up to receive a 944 S2 crown wheel and pinion and an aftermarket Modena LSD. Obviously without the right tools its going to make things a bit difficult, but not impossible.

So we step into the tear down

Step 1.
set the Gearbox up so that it can be worked on
Name:  87.jpg
Views: 5007
Size:  86.0 KB
Step 2
Lock the CV flange with a screw driver and remove the 6mm allen bolts
Name:  86.jpg
Views: 4805
Size:  84.8 KB
Step 3
With a screw driver puncture the rear seal and pry it out
Name:  2.jpg
Views: 4715
Size:  61.8 KB
Step 4
Remove the 17mm gear selector detent
Name:  4.jpg
Views: 4742
Size:  75.9 KB
Step 5
Remove the 3 10mm socket bolts, remove the gear selector plate
Name:  3.jpg
Views: 4760
Size:  77.3 KB

Step 6.Lock the input shaft and select a gear. THis will help lock the Pinion so that you can remove the triple square bolt Behind the Rear seal. Remove the triple square bolt.
Name:  944Translock003.jpg
Views: 4748
Size:  112.8 KB

Name:  7.jpg
Views: 4692
Size:  56.2 KB
Step 7
Now remove all the 6mm allen bolts holding on the rear housing. then tap the rear housing off with a drift. alternate sides with the drift until the housing is removed

Step 8
Remove the 17mm bolt on 5th gear
Name:  8.jpg
Views: 4715
Size:  65.8 KB
Step 9
Use a puller to remove the rear bearing race and part of the 5th gear assembly.

Step 10
Remove the circlip in the 5th gear assembly
Name:  10.jpg
Views: 4756
Size:  78.4 KB
Step 11.
Next remove the 5th gear selector fork dowel with a punch.

Step 12.
With a bit of coercing you can now remove 5th gear.
Name:  12.jpg
Views: 4720
Size:  60.4 KB
Step 13.
Use a 2 arm puller to remove the matched 5th gear. It is easier if you heat the gear up with hot air guns before removal
Name:  13.jpg
Views: 4714
Size:  66.9 KB
Step 14
Remove the shim for 5th gear. you can see it below sitting atop the main shaft bearing.
Step 15
Remove the 2 6mm stop bolts and the 17mm stop bolts and detents on the main carrier case
Name:  16.jpg
Views: 4714
Size:  65.4 KB
step 16
Now remove all of the 13mm bolts holding the main carrier to the diff carrier. Use a drift and tap both sides of the main carrier until it is loose from the diff housing. you can now remove the main carrier with the gearset.
Name:  17.jpg
Views: 4708
Size:  89.8 KB
Step 17
with a punch remove the dowel for 1st/2nd and for 3rd/4th.

Step 18
you can now remove 3rd/4th selector Rod. be careful though as there is a small locking detent which lives in the 3rd/4th selector Rod. when removing you will most likely hear it fall into the main carrier case. you will also find a detent and spring beneath the 3rd/4th selector rod
Name:  19.jpg
Views: 4755
Size:  88.0 KB
Name:  20.jpg
Views: 4727
Size:  83.0 KB
Name:  21.jpg
Views: 4706
Size:  96.7 KB
Step 19
Remove selector Rod Locks with a magnet
Name:  22.jpg
Views: 4719
Size:  74.2 KB
Name:  23.jpg
Views: 4687
Size:  57.1 KB
Step 20
You can now move the pinion forward with 1st/2nd selector rod and now remove the input shaft
Name:  24.jpg
Views: 4890
Size:  83.0 KB
Name:  25.jpg
Views: 4730
Size:  85.7 KB
Name:  27.jpg
Views: 4707
Size:  94.9 KB
step 21
With the pinion removed you can now disassemble it if needed. You will need a press for this. you can see where the circlips are.
Name:  28.jpg
Views: 4731
Size:  85.2 KB
Step 22
Here is the Pinion assembled with new bearings ready to have the pinion preload set. Every time the bearings are replaced the preload will need to be rechecked and modified if necessary. Next photo is of the tools needed to assemble the 944 trans and set pinion preload, pinion depth and diff backlash
Name:  31.jpg
Views: 4747
Size:  73.9 KB

Step 23.
Setting preload. We use the original shims behind the bearing shells to first check pinion preload. remove old bearing shells and replace with the new ones.
Name:  29.jpg
Views: 4748
Size:  71.9 KB
Name:  30.jpg
Views: 4709
Size:  89.2 KB
Step 24
With the Pinion in place and main carrier torqued to the diff case(all bolts) you can now check Pinion preload with a torque gauge as shown. you turn the torque gauge until the Pinion is turning and then take the reading. We use 2.5NM as a good preload. Assemble the shims so that 2.5nm is reached. This may take a few attempts with different shims

Name:  39.jpg
Views: 4724
Size:  58.6 KB
Name:  40.jpg
Views: 5814
Size:  84.6 KB

Last edited by JET951; 03-21-2012 at 05:45 AM.
JET951 is offline  
Old 03-20-2012, 07:25 AM
  #2  
JET951
Addict
Rennlist Member
Thread Starter
 
JET951's Avatar
 
Join Date: Nov 2005
Location: Sydney Australia
Posts: 2,513
Default

Step 25
Next up is pinion depth.
The RO distance for the 944 S2 crownwheel and pinion is 59.65mm. to this we add the "quite running" number on the new crown wheel. In our case you can see here is 0.36mm.
Name:  41.jpg
Views: 3866
Size:  75.7 KB
Step 26
Here you can see us setting the pinion depth tool to our desired level. In our case the number was 60.01mm. We set the dial gauge at 2.5mm depth with the micrometer attached
Name:  42.jpg
Views: 3873
Size:  72.6 KB
Step 27
The pinion is in place and torqued. The Pinion also has a special tool(flat magnet) attached to it. This is so we can use the pinion depth tool against it and get an accurate reading.
The tool in placed where the diff would be placed and the diff case torque down. We now turn the tool until we read a maximum depth. We are trying to get as close to Zero as possible on the gauge.(which is our original 60.01 reading) Usually we get it within .01 of our desired quiet running distance. Remember when obtaining the Quiet running distance you will be moving the pinion forward or backwards. Considering the pinion preload is already set you need to remember if you remove shims from one side of the pinion to move it in a certain direction you must then add the exact same thickness shim(s) to the other side to keep your preload correct. Name:  43.jpg
Views: 3831
Size:  46.9 KB
Name:  44.jpg
Views: 3837
Size:  73.7 KB
Step 28
Assemble the diff with new bearings.(and in our case a new crown wheel and pinion, always use new crown wheel bolts) Its best to heat the Bearing with heat guns to aid in installation.
Name:  35.jpg
Views: 3918
Size:  63.7 KB
Step 29
Setting diff preload
you can now remove the Pinion again. And set the preload as you did with the Pinion. Using shims behind the new diff side shells Install the Diff and you can now set the diff preload to 2.5NM.
Name:  47.jpg
Views: 3835
Size:  84.7 KB
Step 30
Setting Diff backlash.
When setting diff backlash we are looking to obtain .10mm of movement on our dial gauge. this is a very small amount of movement so a dial gauge is needed. This is done with the Pinion torqued onto the diff housing with the main case(but without the gearset). The backlash tool is moved side to side to see the freeplay on the dial gauge. this will take some trial and error to get right.
Name:  49.jpg
Views: 3941
Size:  77.6 KB
Step 31
Time to re assessable the transmission. basic reverse of our disassemble. but a few things to look out for.
Make sure the pin(short arrow) is in the slot (big arrow) for reverse gear. other wise you will have problems.
Name:  50.jpg
Views: 3937
Size:  74.6 KB
Step 32
assemble Pinion with 1st/2nd selector shaft.
Name:  52.jpg
Views: 3838
Size:  94.9 KB
Step 33
Place locks in place and detent underneath 3rd/4th selector rod. Make sure the small lock is in place before 3rd/4th selector rod is installed. i use grease to hold it in place
Name:  53.jpg
Views: 3890
Size:  92.5 KB
Name:  55.jpg
Views: 3807
Size:  100.9 KB
Name:  56.jpg
Views: 3857
Size:  57.1 KB
Name:  60.jpg
Views: 3842
Size:  45.5 KB
Name:  62.jpg
Views: 3870
Size:  74.2 KB
Step 34
install Dowel for 1st/2nd and 3rd/4th selector Rods
Name:  63.jpg
Views: 3837
Size:  61.2 KB
Step 35
install stop bolts
Name:  64.jpg
Views: 3847
Size:  79.0 KB
Step 36
Put shims back on before 5th gear install
Name:  65.jpg
Views: 3827
Size:  51.1 KB
Name:  66.jpg
Views: 3848
Size:  68.2 KB
Step 37
Heat 5th gear and install.(it needs to be hot)
Name:  67.jpg
Views: 3870
Size:  74.6 KB
Name:  68.jpg
Views: 3835
Size:  79.7 KB
Step 38
Install 5th gear set assembly, install dowel, install circlip
Name:  69.jpg
Views: 3855
Size:  60.4 KB
Name:  70.jpg
Views: 3856
Size:  55.4 KB
Name:  71.jpg
Views: 3860
Size:  68.8 KB
Step 39
Heat 5th gear syncromesh ring and install, then heat inner bearing race and install
Name:  72.jpg
Views: 3876
Size:  69.2 KB
Name:  73.jpg
Views: 3824
Size:  68.9 KB
Name:  74.jpg
Views: 3874
Size:  70.8 KB
Step 40
Torque up 5th gear bolt to 70NM
Name:  75.jpg
Views: 3853
Size:  65.8 KB
Step 41
assemble with transmission sealant on gasket and torque together
Name:  76.jpg
Views: 3977
Size:  81.1 KB

Name:  77.jpg
Views: 3893
Size:  71.3 KB
Step 42
Heat up outer bearing race and install
Name:  78.jpg
Views: 3829
Size:  57.7 KB
Step 43
Remove input seal from diff case
Apply transmission sealant to between main case and diff case and torque down.
Name:  775.jpg
Views: 3848
Size:  98.9 KB
Name:  79.jpg
Views: 3820
Size:  80.7 KB
Step 44
install reverse switch
Name:  80.jpg
Views: 3877
Size:  78.5 KB
Step 45
install selector, install selector plate, install top detent

Name:  82.jpg
Views: 3809
Size:  77.3 KB
Name:  83.jpg
Views: 3852
Size:  75.9 KB
Step 46
Install Rear seal, front seal and torque side flanges

Name:  85.jpg
Views: 3843
Size:  82.7 KB
Name:  86.jpg
Views: 3879
Size:  84.8 KB
Trans build now complete
Name:  87.jpg
Views: 6446
Size:  86.0 KB

regards
Sean

Last edited by JET951; 03-20-2012 at 05:54 PM.
JET951 is offline  
Old 03-20-2012, 07:42 AM
  #3  
Thom
Addict
Rennlist Member
 
Thom's Avatar
 
Join Date: Mar 2002
Posts: 4,037
Default

Excellent. Thanks much for that.
Thom is offline  
Old 03-20-2012, 08:04 AM
  #4  
Paulyy
Professional Hoon
Rennlist Member
 
Paulyy's Avatar
 
Join Date: Jan 2010
Location: Melbourne, Australia
Posts: 7,090
Default

nice write up!
Paulyy is offline  
Old 03-20-2012, 08:37 AM
  #5  
Adonay
Addict
Rennlist Member
 
Adonay's Avatar
 
Join Date: Aug 2009
Location: norway and or sweden
Posts: 813
Default

Thank you so much. Have been thinking about doing a aftermarket diff in my gear box, and this has given me a better understanding how the gearbox is put together and if i want to do it my self.
Adonay is offline  
Old 03-20-2012, 08:56 AM
  #6  
67King
Super User
 
67King's Avatar
 
Join Date: Apr 2009
Location: Knoxville, TN
Posts: 3,641
Default

Great write-up! Thanks much for posting that. A few questions for you.
1. The factory manual states 0.30mm should be added to the pinion shim thickness for pre-load, and 0.50mm should be added for carrier shim thickness for pre-load. My experience shows these numbers to be too thick by about 0.15 and 0.10mm, respecitvely. Curious as to your experience?
2. Of the three transaxles I have, one of them (came from an S2) has a shim/plate between the gear housing and rear housing that is probably 8mm thick. I have never seen any references to it elsewhere. I'm curious to know if you've seen this, and if so, any info as to whey itis there? FWIW, the rear housing on that transaxle is shorter by that much. The one that has it is the only one wihtout a cooling loop.
3. Any secrets for removing the triple-square bolt from the back of the input shaft? I eventually got them, but they are bears!
67King is offline  
Old 03-20-2012, 09:05 AM
  #7  
cwigg66
Addict
Rennlist Member
 
cwigg66's Avatar
 
Join Date: Nov 2003
Location: Atlanta
Posts: 332
Default

Amazing writeup. What a valuable resource for everyone. THANKS!
cwigg66 is offline  
Old 03-20-2012, 09:40 AM
  #8  
JohnKoaWood
Super User
 
JohnKoaWood's Avatar
 
Join Date: Dec 2007
Location: Fly Away
Posts: 7,761
Default

Most excellent write up Sean!

I have been back and forth with buying a used LSD box, or installing the LSD I have on hand to my gearbox... Guess I need to start searching for the special tools... as I am sure I will use them more than once!

Originally Posted by 67King View Post
Great write-up! Thanks much for posting that. A few questions for you.
1. The factory manual states 0.30mm should be added to the pinion shim thickness for pre-load, and 0.50mm should be added for carrier shim thickness for pre-load. My experience shows these numbers to be too thick by about 0.15 and 0.10mm, respecitvely. Curious as to your experience?
2. Of the three transaxles I have, one of them (came from an S2) has a shim/plate between the gear housing and rear housing that is probably 8mm thick. I have never seen any references to it elsewhere. I'm curious to know if you've seen this, and if so, any info as to whey itis there? FWIW, the rear housing on that transaxle is shorter by that much. The one that has it is the only one wihtout a cooling loop.
3. Any secrets for removing the triple-square bolt from the back of the input shaft? I eventually got them, but they are bears!
the tans reinforcing plate is available, my understanding is it is used to stabilize the rear of the housing when horsepower is stepped up (V8 swaps, and GT40 replica builds)..

Here is just one source I have found over the years for them.. there are others!
http://www.texasperformanceconcepts....sionparts.html

Last edited by JohnKoaWood; 03-20-2012 at 01:45 PM.
JohnKoaWood is offline  
Old 03-20-2012, 10:27 AM
  #9  
reno808
Super User
 
reno808's Avatar
 
Join Date: Mar 2005
Location: In the garage trying to keep boost down
Posts: 8,809
Default

The fact you made it look that easy shows how hard it is
reno808 is offline  
Old 03-20-2012, 10:32 AM
  #10  
CyCloNe!
Addict
Rennlist Member
 
CyCloNe!'s Avatar
 
Join Date: Dec 2009
Location: Virginia Beach, VA 23464
Posts: 3,243
Default

Excellent Write Up, I honestly Learned a great deal!
CyCloNe! is offline  
Old 03-20-2012, 10:51 AM
  #11  
67King
Super User
 
67King's Avatar
 
Join Date: Apr 2009
Location: Knoxville, TN
Posts: 3,641
Default

Originally Posted by JohnKoaWood View Post
the tans reinforcing plate is available, my understanding is it is used to stabilize the rear of the housing when horsepower is stepped up (V8 swaps, and GT40 replica builds)..
Thanks, John! Had never seen that before. Probably won't need it for my mild SP3 car, but at least I know what it is.
67King is offline  
Old 03-20-2012, 11:11 AM
  #12  
Tom M'Guinn
Addict
Rennlist Member

 
Tom M'Guinn's Avatar
 
Join Date: Jan 2002
Location: Just CA Now :)
Posts: 10,693
Default

Post of the year! Thank you!
Tom M'Guinn is offline  
Old 03-20-2012, 11:14 AM
  #13  
95ONE
Super User
 
95ONE's Avatar
 
Join Date: Sep 2005
Location: TEXAS
Posts: 4,245
Default

Fantastic. Excellent write up. Thank you for your time to do this.

Could an admin please make this a sticky of sort?
95ONE is offline  
Old 03-20-2012, 12:02 PM
  #14  
reno808
Super User
 
reno808's Avatar
 
Join Date: Mar 2005
Location: In the garage trying to keep boost down
Posts: 8,809
Default

Originally Posted by 95ONE View Post
Fantastic. Excellent write up. Thank you for your time to do this.

Could an admin please make this a sticky of sort?
2 things
1. we need a section for this on the 951 section
2. where is testarosa badge
reno808 is offline  
Old 03-20-2012, 01:26 PM
  #15  
944V8inDFW
User
 
944V8inDFW's Avatar
 
Join Date: Apr 2004
Posts: 1,729
Default

Very nice pictures and writeup
944V8inDFW is offline  

Thread Tools
Search this Thread
Quick Reply: 944 Transmission Walkthrough (image heavy)


Contact Us - About Us - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: