Change trans from 5 speed to 4 speed

[bladerunnerkim]

Gday readers, I’ve just had my sons sv6 trans **** itself. Took it to trans place and I’m told it’s a rare 5 speed auto so rare to find and fix, also told weak box. Was wondering if anyone has changed to the 4 speed box, if it’s possible? Any help appreciated, also Merry Christmas to all.

 

[99notout]

I would check another transmission place after the Christmas break, it is just too hard to mate a 4 speed box up to the 190kw motor. Or you could just source a used 5 speed (with guarantee) from a wreckers change it over?

 

[CalaisNQ]

I would be going to a different place too, 5 speed auto is not rare.
what's wrong with the gearbox?
How many kilometres has it done?
Has the auto ever been serviced?
If the auto is stuffed, cheaper to replace with new 5 speed, I don't think you can even fit a 4 speed to the 190kw engine.

 

[bladerunnerkim]

I would be going to a different place too, 5 speed auto is not rare.
what's wrong with the gearbox?
How many kilometres has it done?
Has the auto ever been serviced?
If the auto is stuffed, cheaper to replace with new 5 speed, I don't think you can even fit a 4 speed to the 190kw engine.[/QUOTE

 

[bladerunnerkim]

Gday, had the box pulled apart and clutches all had it. Car has done 255000km and think it’s original so not bad I guess. It’s all been fixed with a partial rebuild now, wasn’t going to pay over $4000 for full reco but still cost $2600 to get that done. Will be serviced regularly from now on.

 

[CalaisNQ]

For that amount k's, yer probably ok, if never serviced in it's life.
Good to see you got fix to your problem.
Years ago I was told by transmission specialist, recommended service intervals no more than 80 thou k's, 60 thou k's, for vehicles towing, stop start traffic all the time, load carrying.
I don't believe in the so called "sealed for life" rubbish, I've had auto do 300-400 thou k's, no problem, following advise.

 

[ozNick]

Agree with above comments.
I would also highly recommend an additional transmission cooler for the 5 speed (PWR make a kit for the VZ).
Also the box recommends synthetic Dexron III but if you're doing the service yourself, I would recommend Dexron VI.

 

[CalaisNQ]

The minimum spec oil for 5 speed auto was Dexron V if I remember correctly , hard to get anything lower than Dexron VI spec trans oil anyway, the high grade better anyway.