Removing the F25 Gearbox in a Saab NG900

We showed you how to remove the F40 transmission from a 9-3SS 2.0T, and how to remove the entire powertrain from a Saab NG900. This time we’ll show you how to take just the transmission out on its own.

Disclaimer: I was far from organized when I started this “how-to.” I hadn’t really planned anything out, so the order may seem a bit off in the video, but I’ll describe the process in the way I think will work best. I also took some assumptions of the reader, so this how-to may not be 100% suitable for the absolute beginner, but if you have some experience in car repair, you’ll do just fine.

As with almost any car project, get that thing off the ground. If you’re lucky you have a lift, if not, grab the jacks, wheel chocks, and jack stands. Once everything is setup give it a nice shake to make sure it’s stable.

Begin by disassembling each of the front corners. This includes removing the calipers, brake pads, and axle nuts. If you plan on removing the struts with the subframe (as we did), detatch the tie rod ends. However, If you plan on leaving the struts in place, the tie rods can stay, but you’ll have to remove the ball joints instead. Alternatively, you can detatch the control arms from the subframe, though I think they’ll be in the way later on.

We built our own custom exhaust for our Saab NG900, so I’m not sure if this step is identical for an OEM setup, but my guess is it’s 99% there. We had to remove our custom downpipe, as well as unplug the rear o2 sensor. For stock exhausts, you will need to unplug the upstream o2 sensor as well. We mounted our downpipe via a v-band clamp a few inches post turbo. It is easier and quicker to remove, we don’t risk breaking the studs on the turbo, and we can leave the upstream sensor in place when removing the exhaust.

These next few steps can be done with or without the subframe in place, but for additional safety and support, I would do them before removing the subframe. On top of the transmission you need to remove the clutch cable (or hydraulic line) from the clutch fork and its mount, unplug the reverse sensor, disconnect the shift linkage, and unbolt two ground cables, one on the front and one on the side of the trans.

At this point the subframe is just about ready to be removed. But first, the rear motor mount nuts need to be removed, and the engine needs to be supported. I used a jack to avoid the legs of the engine hoist getting in the way when removing the transmission. I typically remove the subframe bolts in a ‘front, back, middle’ sequence, but feel free to use whichever order you prefer. Since we chose to leave the struts attached, the subframe was now hanging by the ball joints attached to the strut.

Finally, you need to remove the struts. Use your other hand, a jack, or another person to hold the strut to support the subframe assembly. Remove the three bolts on each strut tower and lower the subframe assembly to the ground. Make sure you pay attention to the CV joints so you don’t accidentally rip a boot on the way down.

I would highly recommend draining the transmission fluid and removing the half-shafts just to make things easier, but it’s not 100% necessary. To remove the intermediate shaft you will need to remove the alternator and lower bracket. To remove the alternator on your Saab NG900 you will need to remove the serpentine belt and tensioner in order to gain access to the top alternator bolt. From there, remove the positive wire, signal wire, top and bottom alternator bolts, and wiggle the alternator free. Finally, remove the lower alternator bracket, intermediate shaft, and passenger half-shaft.

Moving onward, the two starter bolts/nuts need to be removed. The transmission bolts can also be removed, aside for the top two. At this point double check the engine support and remove the transmissions mount.

Starter nut and bolt

From here, begin lowering the jack so that there is enough room to clear the inner fender and remove the transmission. Pay attention to things like radiator and intercooler hoses, fuel lines, etc. to avoid breaking anything as you tilt the powertrain. Finally, using either a person or a jack to support the transmission, remove the final two bolts, wiggle it free, and bring it to the ground.

Congrats! You’ve just removed the F25 transmission from your Saab NG900.

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