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-   -   Cheap Axle Alternative (https://rennlist.com/forums/944-turbo-and-turbo-s-forum/686946-cheap-axle-alternative.html)

blown 944 06-03-2012 09:30 PM


Originally Posted by 95ONE (Post 9583271)
Sure it does. The transaxle always twists a certain way when under acceleration, and over time as the already loose tolerance trans mount wears, it allows more movement. This movement is always the same, twisting more and more as the mount wears, and binds the cage at angles it cant handle. This angle twists and moves in a way that puts more stress on the drivers side. That is why the drivers side is more apt to break.


This^

I have also looked into another reason the axle cages break after many miles and I have come to the conclusion that the cage and ball wear gets to the point where the balls extend past the cage enough to become dis-engaged.

I found this when I heard the axle hitting the outer hub. I am working on a delrin plug that will limit the total lateral travel of the axle shaft so it will remain in the optimum position even when worn.

lejams 06-03-2012 11:17 PM


Originally Posted by blown 944 (Post 9583294)

I have also looked into another reason the axle cages break after many miles and I have come to the conclusion that the cage and ball wear gets to the point where the balls extend past the cage enough to become dis-engaged.

I found this when I heard the axle hitting the outer hub. I am working on a delrin plug that will limit the total lateral travel of the axle shaft so it will remain in the optimum position even when worn.

The cage on my CV hasn't broken in fact it looks to be in pretty good condition. Although in time it may have if I hadn't caught it now. But had it gone onto break, it would have been for the lack of lubrication, and not just typical wear. At 95k I don't have any evidence that there was any excessive side way movement. The end of the axles are unscathed and the wheel hub still has grease in it nice and smooth. The picture is from the CV joint next to the TA. No way the axle could hit in the TA hub because its more funnel shaped and way to deep.

lejams 06-03-2012 11:22 PM


Originally Posted by 95ONE (Post 9583271)
Sure it does. The transaxle always twists a certain way when under acceleration, and over time as the already loose tolerance trans mount wears, it allows more movement. This movement is always the same, twisting more and more as the mount wears, and binds the cage at angles it cant handle. This angle twists and moves laterally in a way that puts more stress on the drivers side. That is why the drivers side is more apt to break.

No offense but there is some conjecture here. All things being relatively equal on both sides of the TA, how do you establish everything always twists in a certain way? How do you know that the movements are always the same and how is it known that it always puts more stress on only the driver’s side? For all practical purposes, my TA mount looked as good as new. After I cleaned it up good, I could not find any cracks or striations of any kind. This is my point.

lejams 06-03-2012 11:32 PM

Regarding cages breaking, there are some known issues with breakage sometimes when people buy a kit and rebuild themselves. Bill & I discussed this and the importance of re-assembling the cages correctly when repairing the joint. Although it’s relatively simple, there is a way the Cross Grooved Joints are to be reassembled that can be overlooked. Because Cross Grooved Joints are cut at an angle, unlike a Double Offset CV Joint which the grooves are cut perpendicular, (or parallel with the axel bar), the orientation of the Outer Housing to the Inner Race must be correct. If not, the cage will definitely break. Attached is a PDF specifying how to re-assemble the joint.

95ONE 06-04-2012 12:35 AM


Originally Posted by lejams (Post 9583597)
No offense but there is some conjecture here. All things being relatively equal on both sides of the TA, how do you establish everything always twists in a certain way? How do you know that the movements are always the same and how is it known that it always puts more stress on only the driver’s side? For all practical purposes, my TA mount looked as good as new. After I cleaned it up good, I could not find any cracks or striations of any kind. This is my point.

Because it does. centrifugal forces, velocity vectors and all those fancy things taking into account rotational and transversal pulls on the transmission when considering the torque from the motor twisting the whole assembly and the "pull" of the axles. Assuming this is happening when accelerating forward and not going in reverse. How exact would you like me to be in explaining this? Same angle and direction of deflection relative to intensity using stock mounting points and tolerance that gets looser with age on both ends. Damage varies with intensity depending on drivers right foot and, well, left foot too, hence your nice looking cages. Things are not equal on both sides of the TA.

lejams 06-04-2012 10:39 PM

95ONE - Thanks for explaining, guess I should have been clearer. I was looking for something more tangible.

lejams 06-04-2012 11:58 PM


Originally Posted by robstah (Post 9586524)
I take it you have never seen an engine twitch to the passenger side during free rev before. Certain BMWs have issues with moneyshifting solely due to the engine twisting enough to cause the user to think he is shifting up, but rather shifting down. Worn motor and trans mounts tend to expedite the situation.

I know that engines and trans-axles shift, (within the tolerance of design). Was just trying to find out, in this case, what is causing things to wear more in one direction than the other. This was designed by Porsche to move laterally. Given that is happening within the designed tolerances, was really trying to find out what if any other parts are wearing and contributing.

acorad 06-05-2012 01:24 AM


Originally Posted by robstah (Post 9586648)
Plus, due to the transaxle mount design, the assembly in the rear doesn't simply twist, but swings towards the driver's side.

Sounds pretty tangible to me.

lejams 06-07-2012 09:16 PM


Originally Posted by V2Rocket_aka944 (Post 9583236)
accurate enough for me, if you get a chance to do it. do it by itself and then (with you holding it - you not holding it) to see if theres any difference with your scale.

Using a digital bath scale, both the original oem & EMPI weigh about the same, i.e. 13lbs.

V2Rocket 06-07-2012 09:50 PM


Originally Posted by lejams (Post 9595176)
Using a digital bath scale, both the original oem & EMPI weigh about the same, i.e. 13lbs.

So who'll be the first to machine up some titanium axles :biggulp:

bouldersyncro 06-25-2012 09:53 PM

Great thread!

I found this thread searching for information about installing 944 axles onto a Vanagon and thought I would throw in my $.02.

Just to be clear, Vanagon axles are 21.25 (540mm) inches long. I think that lejams meant that the 944 axles measured 21 1/8, not 24 1/8.

Anyway, some of us in the 4WD Vanagon Syncro world have lifted our vans for better off road performance and are looking for a CV joint with a greater “Maximum Angularity”. The internet reports that the type 2 CV’s on a Syncro are rated at 17*, whereas the type 4 CV’s on the 944 are rated at 22*.

Thanks to lejams we now know that EMPI claims no variation in maximum angularity exist between the different types of CV’s. However, I replaced one of my stock Syncro axles with the EMPI 90-6805 and noticed that my maximum suspension droop (before the CV starts binding) increased by over an inch with the EMPI axle. So apparently there is some difference in maximum angularity, just maybe not with EMPI CV’s. The EMPI axle also measured 2-3mm thicker than the original Syncro axle. This all seems like good news for those of you running EMPI Vanagon axles on a 944, as they seem to offer a thicker (stronger?) shaft and greater maximum angularity than the original Vanagon shaft.

However the general wisdom of the Syncro community is that EMPI axles and CV’s are not to be trusted off road and are breaking at a significantly higher rate than the OE (GKN/Lobro) axles. These failures are in off road conditions, many times with one wheel off the ground and diff locks engaged and not while on a track (ha!) or daily driving. Being that AAA does not come get me if I break an axle up some Jeep trail I have just bought a pair of new Lobro 944 axles for my Syncro. Ironically new GKN Syncro axles are not available. Once they arrive I’ll compare them to the EMPI and OE Syncro axles and report back.

dmcampbell 06-26-2012 11:23 PM

I found correct part on Parts Geek. Any track use updates on these axles? I need new ones and would rather swap than rebuild. Thanks, Mike

pontifex4 06-27-2012 10:48 PM


Originally Posted by bouldersyncro (Post 9638039)
Great thread!

I found this thread searching for information about installing 944 axles onto a Vanagon and thought I would throw in my $.02.

Just to be clear, Vanagon axles are 21.25 (540mm) inches long. I think that lejams meant that the 944 axles measured 21 1/8, not 24 1/8.

Anyway, some of us in the 4WD Vanagon Syncro world have lifted our vans for better off road performance and are looking for a CV joint with a greater “Maximum Angularity”. The internet reports that the type 2 CV’s on a Syncro are rated at 17*, whereas the type 4 CV’s on the 944 are rated at 22*.

Thanks to lejams we now know that EMPI claims no variation in maximum angularity exist between the different types of CV’s. However, I replaced one of my stock Syncro axles with the EMPI 90-6805 and noticed that my maximum suspension droop (before the CV starts binding) increased by over an inch with the EMPI axle. So apparently there is some difference in maximum angularity, just maybe not with EMPI CV’s. The EMPI axle also measured 2-3mm thicker than the original Syncro axle. This all seems like good news for those of you running EMPI Vanagon axles on a 944, as they seem to offer a thicker (stronger?) shaft and greater maximum angularity than the original Vanagon shaft.

However the general wisdom of the Syncro community is that EMPI axles and CV’s are not to be trusted off road and are breaking at a significantly higher rate than the OE (GKN/Lobro) axles. These failures are in off road conditions, many times with one wheel off the ground and diff locks engaged and not while on a track (ha!) or daily driving. Being that AAA does not come get me if I break an axle up some Jeep trail I have just bought a pair of new Lobro 944 axles for my Syncro. Ironically new GKN Syncro axles are not available. Once they arrive I’ll compare them to the EMPI and OE Syncro axles and report back.

Great first post, and welcome!

lejams 06-27-2012 10:52 PM


Originally Posted by bouldersyncro (Post 9638039)
Great thread!

I found this thread searching for information about installing 944 axles onto a Vanagon and thought I would throw in my $.02.

Just to be clear, Vanagon axles are 21.25 (540mm) inches long. I think that lejams meant that the 944 axles measured 21 1/8, not 24 1/8.

Anyway, some of us in the 4WD Vanagon Syncro world have lifted our vans for better off road performance and are looking for a CV joint with a greater “Maximum Angularity”. The internet reports that the type 2 CV’s on a Syncro are rated at 17*, whereas the type 4 CV’s on the 944 are rated at 22*.

Thanks to lejams we now know that EMPI claims no variation in maximum angularity exist between the different types of CV’s. However, I replaced one of my stock Syncro axles with the EMPI 90-6805 and noticed that my maximum suspension droop (before the CV starts binding) increased by over an inch with the EMPI axle. So apparently there is some difference in maximum angularity, just maybe not with EMPI CV’s. The EMPI axle also measured 2-3mm thicker than the original Syncro axle. This all seems like good news for those of you running EMPI Vanagon axles on a 944, as they seem to offer a thicker (stronger?) shaft and greater maximum angularity than the original Vanagon shaft.

However the general wisdom of the Syncro community is that EMPI axles and CV’s are not to be trusted off road and are breaking at a significantly higher rate than the OE (GKN/Lobro) axles. These failures are in off road conditions, many times with one wheel off the ground and diff locks engaged and not while on a track (ha!) or daily driving. Being that AAA does not come get me if I break an axle up some Jeep trail I have just bought a pair of new Lobro 944 axles for my Syncro. Ironically new GKN Syncro axles are not available. Once they arrive I’ll compare them to the EMPI and OE Syncro axles and report back.

Thanks for correcting my error on the axle length. You are correct and it should have read 21-1/8”.

Interesting about your findings on the differences between the EMPI & GKN/Lobro’s. You may find it beneficial to talk with Bill @ EMPI sometime. Apparently, although the SAE standard on all Cross Grooved Joints as Bill read from the book, is a maximum angularity of 25 degrees. Maybe globally not all manufactures comply for one reason or another? I don’t know under what circumstances, if or how, SAE standards interact globally, but in accordance with your finding, sounds like there can be differences.

I don’t have many miles on the EMPI’s yet, but so far so good. However, even though your use is off-roading, which probably neither manufacture intended to warrant, I’m a little disappointed to hear that the EMPI’s are not meeting some of the same stresses as the Lobro’s.

Reimu 06-27-2012 11:00 PM

How are you guys bracing the trans?


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