[moo]

I have a 91 sierra and looks like I need a new gearbox for it I was wondering if there are any other cars that has a gear box that can be used and maybe even stronger than the original.

[Gwagensteve]

No. Not without changing the engine too.

[bumstein]

It's just me but I'd find another Sierra one on the cheap to get the car going, if need be, and then set about rebuilding the existing one.. Maybe pull it apart, take the bearings down to a bearing place and find good quality ones to pop back in. A good learning experience!!

But that's just me...

[303zuke]

Just for academic purposes, you can upgrade to a "stronger" gearbox, the Vitara 1.6. But it wont be cheap or easy. You will need an adapter such as the LUCKY13, then you will need a plate to support the rear bearing in the Vit box, and make up a jackshaft as the dimensions will be different between the back of the Vit box compared to the 1.3 box. I'd say a lot of buggering around, when a 1.3 box is generally more than sufficient for a 1.3 engine.

This approach is usually more often used as one method of installing a 1.6 engine.

[burls]

I have a spare gearbox if you want to do what bumstink said.