Let's talk CV joint preservation...
12-06-2015, 03:01 PM
#32
Rennlist Member
No George. Different people.
12-29-2015, 11:08 PM
#34
Rennlist Member
Thread Starter
Got the axles from xschop, and they look like they mean business!
Does it matter which side of the CV Joint faces in/out? There is a groove around the outer circumference of the joint (see pic below), and from the few online pictures/videos I can find, it appears the groove-side should be toward the ends of the shafts, like in the picture, and NOT toward the rubber boot flange (even though it looks like a receiving groove for the boot flange). Anyone know for sure?
I've always just replaced the whole axle, so hopefully this is an easy one for those who've done it before.
My old joints have no grooves, and both sets of joints "look" symmetrical, like it doesn't matter which face goes where (with both sides of the inner race tapered to slide over the splines).
(George, xschop is a V8 guy who makes parts like these -- not sure if he has his own website? but if you search his name here you will see his parts in various threads....)
Does it matter which side of the CV Joint faces in/out? There is a groove around the outer circumference of the joint (see pic below), and from the few online pictures/videos I can find, it appears the groove-side should be toward the ends of the shafts, like in the picture, and NOT toward the rubber boot flange (even though it looks like a receiving groove for the boot flange). Anyone know for sure?
I've always just replaced the whole axle, so hopefully this is an easy one for those who've done it before.
My old joints have no grooves, and both sets of joints "look" symmetrical, like it doesn't matter which face goes where (with both sides of the inner race tapered to slide over the splines).(George, xschop is a V8 guy who makes parts like these -- not sure if he has his own website? but if you search his name here you will see his parts in various threads....)
12-30-2015, 11:00 AM
#35
Three Wheelin'
I just read this thread with great interest. Let us know how they hold up.
I had the same problem as Patrick with version 1.0 from Lindsey (drive shaft shop part). They had D.S.S. send me a new set that held up well (thanks Lindsey).
My half shafts and cages are holding up but we are having another problem - we are still losing boots (ripping) and I wonder if I should attach a bar to the transmission. If anyone has an elegant solution please post a photo.
400# Torque
13" Michelin blue slicks (softer than cup's)
Hard trans mount
I had the same problem as Patrick with version 1.0 from Lindsey (drive shaft shop part). They had D.S.S. send me a new set that held up well (thanks Lindsey).
My half shafts and cages are holding up but we are having another problem - we are still losing boots (ripping) and I wonder if I should attach a bar to the transmission. If anyone has an elegant solution please post a photo.
400# Torque
13" Michelin blue slicks (softer than cup's)
Hard trans mount
12-30-2015, 11:54 AM
#36
I now run a solid mount. Although the cabin noise is much louder it doesn't really annoy me - It's still not as loud as I was expecting. My car is more track focused/weekend driver running 300bhp+.
12-31-2015, 12:20 PM
#37
Nordschleife Master
12-31-2015, 04:26 PM
#39
Nordschleife Master
Coming out of T3 at Barber I broke the lower coilover bolt (right rear) at 80+mph, allowing the rear of the car to drop onto the tire. That broke a CV joint and I'm guessing it broke the trans mount as well. I ordered a new racers edge bolt and replaced the CV, but never looked at the trans mount. If was the next event that I started breaking CV's and discovered the trans mount.
12-31-2015, 09:29 PM
#40
Three Wheelin'
Can't find a picture of a CV boot set up like that, but this picture might help...
12-31-2015, 09:49 PM
#42
Three Wheelin'
So I think that the broken cage is mainly a wear issue. Specifically, if the inner race of the CV-joint is pitted from marginal lubrication and age, then the ***** will get stuck in those pits under hard acceleration, which will result in extreme stresses in the cage, when the CV-joint angle needs to change (bumps or pot holes).
Laust
Haven't yet used it on CV's, but the best industrial coupling grease I have used is Falk LTG:
http://www.rexnord.com/ContentItems/...duct-Sheet-pdf
From the datasheet:
" re-lube intervals for sensitive gear couplings have been extended from six months to three years."
"Falk Steelflex Grid Couplings are warranted for
five years and Falk Lifelign Gear Couplings for
three years when LTG is used. If other approved
coupling greases are used, our standard one-year
warranty applies to both coupling designs."
five years and Falk Lifelign Gear Couplings for
three years when LTG is used. If other approved
coupling greases are used, our standard one-year
warranty applies to both coupling designs."
CV lubrication requirements are fundamentally different to wheel bearings, so be wary of "multipurpose" greases...
Cheers,
Mike
01-01-2016, 03:25 AM
#43
Three Wheelin'
I broke three CV joints over two track days (all drivers side inboard). At first I thought it was the new engine (468# torque) but then discovered that I had broken two bolts off the transmission hanger (xchops), allowing the trans to move. CV's were breaking due to binding. I decided to hard mount the xchop mount as well as add the extra insurance of a stabilizer (not elegant, see pic). Since then I have had no issues, I am running the empi 90-6805.
01-07-2016, 07:41 PM
#44
Three Wheelin'
Summary:
- Swepco Moly Grease #101
- Every manufacturer makes the cages too tight, causing fractured cages. Relieve the cages so the ***** just fall through.
- On GKN/Lobro joints the ***** are slightly oversized and bind slightly - replace with smaller.
- Use ti-wraps around the minor diameter of each boot bellows to prevent boot failure.
- Vent the CV joint boots so they can breathe with CV movement.
- Don't clamp the boot minor diameter - no functional need.
Cheers,
Mike
01-15-2016, 10:22 PM
#45
Rennlist Member
Thread Starter
As is my way, here is an update on my CV joint/tranny mount project. I went with xschop's mount and axles, with the EMPI 98-5084-B CV joints, and Loebro boot kits from Pelican.
So far, the combo is working great. There may be a hint more vibration in the cabin from the semi-solid mount, but just a hint if any. Vibration is not a reason to avoid this mount for sure. As for noise, there is more gear noise. Hard to quantify, but would describe it as fairly minimal but loud enough to notice the difference. It's not obnoxious and if you never sat in a 951 before, you'd probably just think that's how they are. I'd put it on par with a 911 of similar vintage. Gear changes are noticeably sharper, with a more direct mechanical engagement into and out of gears. Big improvement for sure there.
Pictures and installation info to follow....
So far, the combo is working great. There may be a hint more vibration in the cabin from the semi-solid mount, but just a hint if any. Vibration is not a reason to avoid this mount for sure. As for noise, there is more gear noise. Hard to quantify, but would describe it as fairly minimal but loud enough to notice the difference. It's not obnoxious and if you never sat in a 951 before, you'd probably just think that's how they are. I'd put it on par with a 911 of similar vintage. Gear changes are noticeably sharper, with a more direct mechanical engagement into and out of gears. Big improvement for sure there.
Pictures and installation info to follow....