Forum Home Forum Home > CJ-2A Discussion Area > Modifications from original
  New Posts New Posts RSS Feed - TeraFlex Low 18 3.15 gears in Dana Spicer Model 18
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

TeraFlex Low 18 3.15 gears in Dana Spicer Model 18

 Post Reply Post Reply Page  123>
Author
Message
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Topic: TeraFlex Low 18 3.15 gears in Dana Spicer Model 18
    Posted: 15 Jan. 2019 at 10:04pm
Started to put a D18 transfer case together to see if I can go slower. This all started last year when I took my '48 CJ2A 4-wheeling at the Spring Willys Reunion. A group of us had a blast slippin' and slidin' in the woods. I thought it would be great to have a little more control in a few spots, so started looking into lower gears.
In an ironic twist, I had swapped lower gears in my '79 CJ7 several years ago. To do that, I took the gears out of a D18 and added them to that rare, unicorn of gears - a Bronco Dana 20 sliding gear. Thie changed my gear ratio from 2.03 to a 2.46. It made a HUGE difference crawling. I kept the Dana 18 donor case so I would have something to trip over in the corner of the shop. The ironic part is that I finally took that old case to the very same Willys Reunion and sold it for way dirt cheap. Here it turns out that the case, from a '71 V6 CJ5, was the rare case I needed to swap the TeraFlex low gears into! At least I also scored the unique Dana 44 flanged, offset rear axle.
Well, I couldn't find a similar case, so I ended up getting a large hole donor case from a mid - 70s CJ5 Dana 20. And of course, I had to find a Dana 18 front and rear bearing retainer, shift forks etc, so I ended up buying another whole Dana 18 case. Thankfully, I will have something else to trip over in the corner of the garage again .

Edited by bobevans - 15 Jan. 2019 at 10:39pm

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan. 2019 at 10:19pm
First problem with this case from a Dana 20 is the oil fill plug. The location interferes with rear bearing retainer/parking brake and you can't get to it to fill it! The solution is to tap a new fill hole and plug the old. The D20 fill pan had just the right low profile, recessed square hole 1/2" NPT plug. I ran the tap into the case a little further and ran the plug into the 1/2 NPT die a couple of times to get a deeper fit. Then we had to drill and tap a new fill hole. I couldn't bring myself to drill into the case with a nearly 3/4" drill bit, so I stepped the size down to a 3/8 NPT hole. I used the thick boss where my Spicer 18 case fills now. As Luck would have it, this case was already tapped for clutch pivot stud and a place-holder bolt was keeping the threads clean.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan. 2019 at 10:27pm
Next challenge occurred (if we don't count the hassle of removing and replacing the output shaft bushing) when reassembling the front bearing retainer. The TeraFlex instructions say to remove 1/2" of the shorter shift rail to avoid interference with the intermediate gear. Taking a whole 1/2" off seems like that when the shift rod is all the way forward, the rear part of the shift rod would pretty much come clear out of the main case. I guess we'll have to go real slow and keep trying it in and out. It will def. hit the intermediate gear now, and I guess I'm going to have load up all the needle bearings and actually place the intermediate gear for a final check.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan. 2019 at 10:34pm
The instructions don't mention an interference with the underdrive shift fork (the bigger fork) and the output shaft sliding gear. Especially when I had mechanic's wire on the fork nut, the gear hits the collar of the shift fork. I have 2 different forks and both of them hit the gear. I'm going to clearance the collar of the shift fork, unless some one has a better idea. I think I will also use the later allen head set screw in the fork.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
Lee (MN) View Drop Down
Member
Member
Avatar

Joined: 12 Aug. 2008
Location: Harris, MN
Status: Offline
Points: 3449
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lee (MN) Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jan. 2019 at 10:50pm
Nice!.... How did you get the case so clean ?. Looks like fresh casting! πŸ‘

Lee
               LEE
44 GPW-The Perfected Willys
49 2A
67 M715
American Made Rolling History
Back to Top
Stev View Drop Down
Member
Member

Sponsor Member

Joined: 27 July 2016
Location: Cincinnati
Status: Offline
Points: 1304
Post Options Post Options   Thanks (0) Thanks(0)   Quote Stev Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 8:26am
Very impressive work.  Cant wait to see this Jeep on the trail.  
Stev
1946 CJ2A Trail Jeep, 1948 CJ2A Lefty Restored
Back to Top
AKoller View Drop Down
Member
Member

Sponsor Member

Joined: 18 Sep. 2018
Location: Moundridge Kans
Status: Offline
Points: 85
Post Options Post Options   Thanks (0) Thanks(0)   Quote AKoller Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 9:34am
Thanks for the post. I am planning on a Terralow upgrade this year on my Jeep. I have a big mouth (4") Dana 18 out of a late 60's CJ5 I will use. I will also replace the 2nd gear and synchro's in my T90 at that time to try to solve the jumping out of 2nd problem I currently have. I hope to have this done before the FCT in September if I'm lucky enough to get drawn to go.
1950 CJ3A "Thumper"
1966 M151 A1
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 9:15pm
Originally posted by Lee (MN) Lee (MN) wrote:

Nice!.... How did you get the case so clean ?. Looks like fresh casting! πŸ‘

Lee



The machine shop right next to my office has a "hot tank". The same washing cabinet he uses for engines. Case, bearing housings, shift rods etc. were $30.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
Lee (MN) View Drop Down
Member
Member
Avatar

Joined: 12 Aug. 2008
Location: Harris, MN
Status: Offline
Points: 3449
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lee (MN) Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 10:07pm
Originally posted by bobevans bobevans wrote:

Originally posted by Lee (MN) Lee (MN) wrote:

Nice!.... How did you get the case so clean ?. Looks like fresh casting! πŸ‘

Lee



The machine shop right next to my office has a "hot tank". The same washing cabinet he uses for engines. Case, bearing housings, shift rods etc. were $30.


That’s cheating! πŸ‘πŸ‘πŸ½πŸ‘

Lee
               LEE
44 GPW-The Perfected Willys
49 2A
67 M715
American Made Rolling History
Back to Top
Ol' Unreliable View Drop Down
Member
Member
Avatar

Joined: 25 Sep. 2016
Location: CO Springs CO
Status: Offline
Points: 2894
Post Options Post Options   Thanks (0) Thanks(0)   Quote Ol' Unreliable Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 11:07pm
I see the nearly-ubiquitous Harbor Freight special 27-LED portable worklight there.  Those are the best things HF has ever given away!  Thumbs Up
There's a reason it's called Ol' Unreliable
Back to Top
JeepFever View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 07 Aug. 2012
Location: VA
Status: Offline
Points: 1568
Post Options Post Options   Thanks (0) Thanks(0)   Quote JeepFever Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jan. 2019 at 11:47pm
Originally posted by Lee (MN) Lee (MN) wrote:



That’s cheating! πŸ‘πŸ‘πŸ½πŸ‘
 
 
  I was thinking same thing.  LOL     
 
Looking forward to the "rest of the story"
Back to Top
ndnchf View Drop Down
Member
Member
Avatar
Sponsor Member x 2

Joined: 22 Sep. 2017
Location: Virginia
Status: Offline
Points: 1459
Post Options Post Options   Thanks (0) Thanks(0)   Quote ndnchf Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 6:31am
Originally posted by Ol' Unreliable Ol' Unreliable wrote:

I see the nearly-ubiquitous Harbor Freight special 27-LED portable worklight there.  Those are the best things HF has ever given away!  Thumbs Up

The current light has a single bar LED rather than a bunch of individual LEDs.  Also their freebie little pocket flashlight has gone to single, very bright LED rather than a bunch of small ones.  It is brighter and more focused.  Constant product improvementWink
1948 CJ2A - It goes nowhere fast, but anywhere slow.
Back to Top
oldtime View Drop Down
Member
Member
Avatar

Joined: 12 Sep. 2009
Location: Missouri
Status: Offline
Points: 1415
Post Options Post Options   Thanks (0) Thanks(0)   Quote oldtime Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 7:51pm
Bob you and Steve got me all excited on this topic so I decided to put another one of my transfer cases together today.
This one is going to be a big hole D18 with a Tera low gear set plus tapered Intermediate shaft bearings.
Parts were all setting since last fall and ready to assemble.

Quote  The TeraFlex instructions say to remove 1/2" of the shorter shift rail to avoid interference with the intermediate gear.
I don't have any instructions but found that my large intermediate gear barely clears the short shift rod with the poppet ball engaged into its position.
When I get back at it tommorrow I think that I'll cut 1/8" of from the short shift  rod.
Yes the intermediate gear and the out put shaft must be in their proper positions to determine the working clearance.
My big sliding gear just cleared the large shift fork so I left the fork "as is" without additional grinding.

By the way Bob, those are great pics that you posted.
I can see what it takes to get a camera along with good lighting into that confined space.

I'll probably button mine up tomorrow...






Currently building my final F-134 powered 3B .
T98-A Rock Crawler using exclusive factory parts and Approved Special Equipment from the Willys Motors era (1953-1963)
Zero aftermarket parts

Back to Top
Mike F View Drop Down
Member
Member
Avatar

Joined: 12 Aug. 2018
Location: Longview wa
Status: Offline
Points: 587
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike F Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 8:21pm
I think I’ve decided I need one of these. Along with a T90C and 4.11 gears in the axles

Edited by Mike F - 17 Jan. 2019 at 8:23pm
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 9:03pm
Originally posted by Lee (MN) Lee (MN) wrote:

Originally posted by bobevans bobevans wrote:

Originally posted by Lee (MN) Lee (MN) wrote:

Nice!.... How did you get the case so clean ?. Looks like fresh casting! πŸ‘

Lee



The machine shop right next to my office has a "hot tank". The same washing cabinet he uses for engines. Case, bearing housings, shift rods etc. were $30.


That’s cheating! πŸ‘πŸ‘πŸ½πŸ‘

Lee

Wait, did I say hot tanked? I meant to say I scrubbed the case clean with a toothbrush. Yeah. An NOS, natural hog hair bristles toothbrush. And Murphy's Oil Soap. Yeah, that's what I meant to say.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 9:06pm
Originally posted by oldtime oldtime wrote:

Bob you and Steve got me all excited on this topic so I decided to put another one of my transfer cases together today.
This one is going to be a big hole D18 with a Tera low gear set plus tapered Intermediate shaft bearings.
Parts were all setting since last fall and ready to assemble.

[quote]Β <span style=": rgb248, 248, 252;">The TeraFlex instructions say to remove 1/2" of the shorter shift rail to avoid interference with the intermediate gear.
</span>
<span style=": rgb248, 248, 252;">I don't have any instructions but found that my large intermediate gear barely clears the short shift rod with the poppet ball engaged into its position.</span>
<span style=": rgb248, 248, 252;">When I get back at it tommorrow I think that I'll cut 1/8" of from the short shiftΒ  rod.</span>
<span style=": rgb248, 248, 252;">Yes the intermediate gear and the out put shaft must be in their proper positions to determine the working clearance.</span>
<span style=": rgb248, 248, 252;">My big sliding gear just cleared the large shift fork so I left the fork "as is" without additional grinding.</span>
<span style=": rgb248, 248, 252;">
</span>
<span style=": rgb248, 248, 252;">By the way Bob, those are great pics that you posted.</span>
<span style=": rgb248, 248, 252;">I can see what it takes to get a camera along with good lighting into that confined space.</span>
<span style=": rgb248, 248, 252;">
</span>
<span style=": rgb248, 248, 252;">I'll probably button mine up tomorrow...</span>
<span style=": rgb248, 248, 252;">
</span>
<span style=": rgb248, 248, 252;">
</span>
<span style=": rgb248, 248, 252;">
</span>




Great! I must have read and re-read your transfer case information about a dozen times so far.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
Lee (MN) View Drop Down
Member
Member
Avatar

Joined: 12 Aug. 2008
Location: Harris, MN
Status: Offline
Points: 3449
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lee (MN) Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jan. 2019 at 10:58pm
Originally posted by bobevans bobevans wrote:

Originally posted by Lee (MN) Lee (MN) wrote:

Originally posted by bobevans bobevans wrote:

Originally posted by Lee (MN) Lee (MN) wrote:

Nice!.... How did you get the case so clean ?. Looks like fresh casting! πŸ‘

Lee



The machine shop right next to my office has a "hot tank". The same washing cabinet he uses for engines. Case, bearing housings, shift rods etc. were $30.


That’s cheating! πŸ‘πŸ‘πŸ½πŸ‘

Lee

Wait, did I say hot tanked? I meant to say I scrubbed the case clean with a toothbrush. Yeah. An NOS, natural hog hair bristles toothbrush. And Murphy's Oil Soap. Yeah, that's what I meant to say.


That’s more like it! πŸ˜‚πŸ˜‚πŸ˜‚

Lee
               LEE
44 GPW-The Perfected Willys
49 2A
67 M715
American Made Rolling History
Back to Top
bobevans View Drop Down
Member
Member
Avatar

Joined: 31 July 2005
Location: Pittsburgh, PA
Status: Offline
Points: 443
Post Options Post Options   Thanks (0) Thanks(0)   Quote bobevans Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jan. 2019 at 12:51am
Ken, You're not missing much if you don't have the TeraFlex directions. There is this little intro and then the rest of the directions are 2 pages of reprints of a Haynes or Chilton manual.

'48 CJ2A

'56 DJ3A

'79 CJ7

And two of them actually run!
Back to Top
 Post Reply Post Reply Page  123>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.