'94 VR - Transmission & Drive shaft Repair

[DruiD]

Hi folks,
I was having problems with my Auto, in my '94 VR Exec. I was loosing reverse and slipping out of gears and it wasn't changing gears properly. I knew I was up for a Exchange Transmission, that was fine.

Local Auto transmission shop, swapped in Transmission for $1700, noticed that my Driveshaft wasn't balanced and was out of "phase". Something about most cars being 90 degrees, but commodores should be 30 degrees.

My problem is that I have just got it back from the mechanic, it still shudders -even- after then replacing the driveshaft, universal joints and various other drive line parts - along with the Auto, it doesnt feel too crash hot either.

I was pretty sure that a VR has the electronic gearbox that overrides and changes up (with enough acceleration etc) to 2nd, 3rd etc even if you lock it in 1st. Basically, I still have these problems below, after about $2400 worth of repairs.

1) Drive shaft vibration \ shudder when accelerating. Should this not have been fixed with replacemnet driveshaft, universal joints etc???

2) Transmission seems to be rather quick off the start and does change gears okay if you treat it VERY GENTLY etc but at all times has this strange feel when accelerating, the car has what can only been called a "sandy" or "rough" feel acceleration, i'm wondering if its driveline related, diff or in the transmission still.

3) Transmission seems to often pull intself into or surge into 2nd, only to drop back in power once in second, BUT sometimes its a hard "CLUNK" into 2nd & 3rd.

4) Front a stand still, ACCELERATE flat to the floor - the gearbox holds the gear, in 1st to like 85kms\hr 6,500RPM or more. My friends VR - changes at about 4,500 rpm in the same situation, yet I have to take my foot off the accelerator to let it change up to 2nd. I dont believe I used to have that problem in my old gearbox.

Basically, its not really an issue to take this back to the mechainic, its fully covered, but I want to be sure of my self - and how do you say your mechanaic - "when i really TAKE OFF AND FLOOR IT.. it has this problem...."

Any suggestions or thoughts?

 

[Juzzy]

hey druid, from a apprentice mechanics point of view,i would be asking the transmission lads for a list on what was done to the auto :thumbsup: it should not be running that badly if it has been recondition,even with an out of phased tailshaft.
cheers
justin

 

[DruiD]

hey druid, from a apprentice mechanics point of view,i would be asking the transmission lads for a list on what was done to the auto :thumbsup: it should not be running that badly if it has been recondition,even with an out of phased tailshaft.
cheers
justin

Okay, well my mechanic sent my gearbox away and got a refurbished one in place (apparently all fitted out) which he then fitted. Not sure if I would be able to get the history on the Recondiditoned unit.

So the shudder I am experiencing - would that be from a dodgy \ faulty tailshaft or universal joint etc? Even though they say its been fixed with a fully balanced, in-phase, talishaft etc?

 

[DruiD]

Anyone else got any other ideas, for example - do the problems i outlined above, match up with the parts that where supposed to have been fixed?

 

[thorpey]

if it vibrates sometimes its the auto being too high at the rear mount. you can put spacers there to make it on less of an angle with the shaft. i take it that the car doesnt have IRS being an exec, vibration is a common problem, its ok when your driving normally but under load it sounds like your shaft is gonna fall off.

 

[jamie227]

I have a vs 95 model non irs which has possibly the same clunking sound when i change from drive back to 3rd gear whilst doing about 60/kh, even so when i just tap the accelerator at any speed there seems to be a loud clunking sound coming from what i think is the gearbox, my uncle is a mechanic and he has already checked the tailshaft and uni's and said it might be coming from the diff, he didnt spend alot of time looking at it so ill have to do some more research and get him to have a proper look