HSV GTS VT1 Tailshaft

[bobvhsa]

My VT1 GTS with T56 has a vibration on acceleration that is getting worse. Being a mechanic I pulled the 2 piece tailshaft out to give it an overhaul. It seems to be a quite rare unit. Apart from having standard cross type uni's at both ends ( Round steel flange at Diff, Sliding yoke at T56. No rubber flanges) it also has a Harmonic balancer at the very front directly behind the Gearbox. The HSV dealers can find no record of this Balancer in the parts listings present or historic. The Balancer has started to split its rubber so it needs replacing and could be the cause of the vibration. Has anyone seen these GTS shafts before and can they help with rounding one up. The Driveshaft specialists that I have spoken to have also never seen one before.

 

[Darcon666]

Your Holden/HSV dealers are just A--holes that could not care 1 bit about Holden let alone that you have a HSV. I believe you are talking about the Rubber coupling at the front of a 2 piece tailshat... See attached that may help you with terminology used... Good Luck.

 

[Immortality]

Can you post a picture of said drive shaft?

 

[bobvhsa]

Your Holden/HSV dealers are just A--holes that could not care 1 bit about Holden let alone that you have a HSV. I believe you are talking about the Rubber coupling at the front of a 2 piece tailshat... See attached that may help you with terminology used... Good Luck.

No, its definitely a steel Harmonic balancer with bonded rubber (just like on the front of a engine) pressed on to the steel tailshaft tube with a std uni joint with a steel splined sliding yoke. Centre bearing is std. Diff coupling is std steel round VT1.
I will get a photo next time it is on the hoist. Never seen one like it before and I have changed many of the Rubber coupling type on the VT clubsport I used to have.
Many things are different about these VT 1 GTS's. eg..LT1 Camaro pull clutch from HSV factory, different T56 shift internals to VT2.
You are right - The dealers have no clue anymore.

 

[bobvhsa]

Can you post a picture of said drive shaft?

Yes, I'll get a picture when its on the hoist next week. Maybe its a mod but I bought the car at very low k's and nothing else on the car was modified.

 

[BowTie]

Tailshaft polariser?

 

[_R_J_K_]

Apart from having standard cross type uni's at both ends ( Round steel flange at Diff, Sliding yoke at T56. No rubber flanges) it also has a Harmonic balancer at the very front directly behind the Gearbox.

I believe you are talking about the Rubber coupling at the front of a 2 piece tailshat...

The uni type tail shaft was standard on VT S1s (and possibly S2 V6). The massive round metal weight on the yoke was common on a bunch of VN-VS T5 Commo tail shafts, but not sure for which models in particular. From what I remember the T56 that was mated to the 304 is an earlier, much more bitsa box than the version that came with the LS, so there's a few oddities for it, particularly like you said with the clutch. Likely the length of it to accommodate that T56 and a 304 does make it rare though.

This T56 is a super uncommon HSV only option (for the 215i/225i HSV 304 based 5.7s only I believe) so I doubt it will appear in any FSMs (and the ones from before don't look to be for a 304).

Falcon version of the T5 yoke: Ford ED-EF-EL-AU 6 cyl T5 5 speed tailshaft yoke | eBay
Early T5 tailshafts: VP VR VN VS V6 COMMODORE MANUAL T5 UTE WAGON STATESMAN TAIL SHAFT TAILSHAFT | eBay
VT uni tailshaft: Commodore VT V6 Tail shaft To Suit Station Wagon | eBay

 

[Immortality]

Interesting. Not seen that before. Seen plenty of weights on the end of the T5 extension housing and clutch fork but never on the slip yoke itself.

 

[_R_J_K_]

On the T5 I have in my garage there's a corresponding bracket that extends to the back of that weight that stops tailshaft coming out, I have no idea why they thought it was necessary.

 

[bobvhsa]

The uni type tail shaft was standard on VT S1s (and possibly S2 V6). The massive round metal weight on the yoke was common on a bunch of T5 Commo tail shafts, but not sure for which models. From what I remember the T56 that was mated to the 304 is an earlier, much more bitsa box than the version that came with the LS, so there's a few oddities for it, particularly with the clutch. Likely the length of it to accommodate that T56 and a 304 does make it rare though.

Falcon version of the T5 yoke: Ford ED-EF-EL-AU 6 cyl T5 5 speed tailshaft yoke | eBay
Early T5 tailshafts: VP VR VN VS V6 COMMODORE MANUAL T5 UTE WAGON STATESMAN TAIL SHAFT TAILSHAFT | eBay
VT uni tailshaft: Commodore VT V6 Tail shaft To Suit Station Wagon | eBay

All very interesting. I may have to try getting the shaft balanced with the weight removed and see how that goes. I can see that the bonded rubber section is faulty making the weight slightly movable and probably well out of balance.