Is it over? (Differential)

StrayBassist

Well-known member
Joined
Nov 1, 2024
Location
Sacramento, California
TDI
98 New Beetle ALH
Recently my girlfriend has been borrowing my car for work, and since she works all over the state she's put a ton of miles on the car.. Unfortunately, today, on the way home she went to do a hill start, described the noise as "sounding like something letting go" before the car no longer transmitted power to the wheels in any gear, and made a metal grinding noise when moving (even with the clutch in/shifter in neutral). Putting it in gear and revving makes the speedometer rise as if it's moving, but no power is being put to the wheels at all and a loud metal crunching sound is audible.

My assumption is that the differential blew up, but I'm also not super familiar with the drivetrain beyond the engine and gearbox itself on these cars..
 

csstevej

Top Post Dawg
Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,glutton for punishment got another tdi 2001NB,another yellow tdi NB , added an 06 NB DSG
^^^^ what he said.
 

agent_jwa

Well-known member
Joined
Feb 9, 2024
Location
WI
TDI
02 Golf
Probably just a cv joint, whole axle was $45 on Rock Auto last time I did one. Full axle is cheaper then boots, how idfk
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, MA. USA
TDI
2015 GSW 6M in S trim the other oil burners: 1967 two stroke Sonett 1988 Bolens DGT1700
Could, not as likely, but could, be the spider gears or side gear inside the differential.
Axles are external, thus more easily viewed for their present condition and more likely to have failed. A constant velocity joint is likely, but would have had bad shaking felt before final separation. I've also stripped the splines out of the outer axle stub in the drive wheel hub.
 

StrayBassist

Well-known member
Joined
Nov 1, 2024
Location
Sacramento, California
TDI
98 New Beetle ALH
Got the car up today and had a look, the CV axle has separated at where it bolts in, and dumped all of its grease on everything it could... but it separated very uniquely; the screw holes seem undamaged, they all still have thread, and the screws are all still in the axle but some have backed out slightly, and the rest are just loose but still there.. the axle has kind of tucked itself in an odd position and I don't own any triple-square bits/sockets, so I have yet to pull it out and inspect it up close but it seems like I might be able to just.. pack grease in there, bolt it back in and call it a day. I don't even think I'll need to replace the boot. Anything I should look for before slapping this thing back on?
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
Common problem, somebody didn't torque the bolts correctly.

The factory service manual calls for new bolts and gasket and 40g of grease, but you can get away with reusing bolts and gasket if they are not chewed up. Clean the flange threads thoroughly and torque bolts initially to 10Nm diagonally then to 40Nm.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, MA. USA
TDI
2015 GSW 6M in S trim the other oil burners: 1967 two stroke Sonett 1988 Bolens DGT1700
the CV axle has separated at where it bolts in, ... but it separated very uniquely;
..... the screws are all still in the axle but some have backed out slightly, and the rest are just loose but still there..
o_O Huh?!?
backed out "slightly", but separated so that
.... the car no longer transmitted power to the wheels in any gear, and made a metal grinding noise....
I have concerns that the bolts that were last to unthread were stressed (torque bending) beyond limits and may be compromised. I do not recommend re-using those 6 bolts. Replace them all.
then add some grease, reassemble and torque to the specification.
 

StrayBassist

Well-known member
Joined
Nov 1, 2024
Location
Sacramento, California
TDI
98 New Beetle ALH
o_O Huh?!?
backed out "slightly", but separated so that
Heh, sorry for my poor explanation. I meant to say that they've all backed out and are just sitting in the holes in the CV axle, but some of them look like they nearly fell out and others are still pretty far forward if that makes sense?

By "Gasket," do you guys mean the boot, or is there a gasket I might be missing? I'll try to look for the screws, though I doubt any local parts store would have them.. A little snap ring seems like it fell out, so I'll need to figure out where that goes too..
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
The snap ring secures the CV joint to the axle shaft (18). The self-adhesive gasket is between the CV joint and the transmission flange (17).
 

StrayBassist

Well-known member
Joined
Nov 1, 2024
Location
Sacramento, California
TDI
98 New Beetle ALH
It looks like most of the ball bearing balls fell out of the axle when it let go, and one of the bolts sheared off while the rest are fine. I'm going to take this opportunity to go to my local junkyard and pull an OEM control arm off a car there, reusing the boots from whatever cheap Chinese axle the previous owner put on here. Then I'll likely have to journey to a dealership for a gasket.. I'm looking for part number 8D0407309, right? IDParts recommends it, but the VW website insists it's only for the 2.0L 2003+ cars..
 
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Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, MA. USA
TDI
2015 GSW 6M in S trim the other oil burners: 1967 two stroke Sonett 1988 Bolens DGT1700
Paper gasket #17? Not absolutely critical in my opinion. The 'self-adhesive' is nonsense as it won't stick to the previously greased face I was never able to clean well enough. That and the paper is invariably folded and creased and won't return to a shape that can seal the fitment location. A better seal is possible with NO gasket than with a wrinkled paper gasket.

Regarding re-built axles: Confirm the belville washers # 5 and 15 in the diagram are installed with the raised outer periphery outward toward the joints, and the raised inner diameter at the axle. Confirm the two joints are tight against their retainer clips #3 and 18. These two spring washers maintain a pre-load to reduce any 'slide hammer' effect as the axle extends and shortens as the suspension moves.
You'd think the washers' orientation would be a 50:50 chance of being right, but the aftermarket re-builder assemblers seem to intentionally install them upside down so as to not have to compress them to fit the clip.
 

StrayBassist

Well-known member
Joined
Nov 1, 2024
Location
Sacramento, California
TDI
98 New Beetle ALH
Paper gasket #17? Not absolutely critical in my opinion. The 'self-adhesive' is nonsense as it won't stick to the previously greased face I was never able to clean well enough. That and the paper is invariably folded and creased and won't return to a shape that can seal the fitment location. A better seal is possible with NO gasket than with a wrinkled paper gasket.

Regarding re-built axles: Confirm the belville washers # 5 and 15 in the diagram are installed with the raised outer periphery outward toward the joints, and the raised inner diameter at the axle. Confirm the two joints are tight against their retainer clips #3 and 18. These two spring washers maintain a pre-load to reduce any 'slide hammer' effect as the axle extends and shortens as the suspension moves.
You'd think the washers' orientation would be a 50:50 chance of being right, but the aftermarket re-builder assemblers seem to intentionally install them upside down so as to not have to compress them to fit the clip.
Alright, sweet. Saves me borrowing someone's car to make 45-minute trip to the closest dealer that has the gasket in stock...

I'll be pulling the axle off a junkyard car, so I suspect it's pretty likely it'd be the factory one. I don't have the money right now to order a properly rebuilt one or new aftermarket one. Should I still inspect the washers and joints against the retainer clips?

Two dumb questions; guy at the auto parts store sold me wheel bearing grease insisting it's the same as CV axle grease... was he just being lazy or is that accurate? And should I go in there with degreaser and shop towels to really clean up everything out of the spot the inner part of the CV axle bolts up to, or is it fine to leave the old grease on there? Sorry for my naivety, most of my experience is working on engine and transmission components, everything else in the drivetrain after that and suspension stuff is kinda new to me..
 

fatmobile

Veteran Member
Joined
Jul 16, 2019
Location
north iowa
TDI
an ALH M-TDI in a MK2, a 2000 Jetta, 2003 wagon
Nice.
Glad you had a salvage yard you could get a good stock factory axle from.
Pretty easy fix.
Easier than changing the transaxle.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, MA. USA
TDI
2015 GSW 6M in S trim the other oil burners: 1967 two stroke Sonett 1988 Bolens DGT1700
Too late, but re: post #14....
Wheel bearing grease has to cope with heat from the proximity to the brakes. The bearing run in one track forever.
C/V grease is typically subjected to less heat (see item #20 in the post #11 insert for the exception) but the balls have a much larger running area due to suspension and steering angles.
I have separate greases for each application.
If the boots are undamaged, and the take-off OEM axle was removed mere hours prior (not sitting out, open, in the weather for who knows how long) I'd leave the C/V grease.
 

fatmobile

Veteran Member
Joined
Jul 16, 2019
Location
north iowa
TDI
an ALH M-TDI in a MK2, a 2000 Jetta, 2003 wagon
Pretty sure you can use moly grease.
Contains molybdenum.
It looks the same as factory axle grease and is extreme pressure.
An old euro mechanic told me so.
 
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