Pinion Gear

[idiot_saabvant]

Is the pinion gear for a C900 5/4 spd the same for all tranny years or did it change in 89 when SAAB went to a larger pinion bearing, or later say 91?

I took a corner to fast, and the inner face of my ring/crown gear is chipped every 5th or 6th groove. Rumor has it this is a cause from diff case flex. I have one of Luke's steel diff covers, but it was not installed at the time.

I also understand that the pinion/ring gear is a matched set, so just replacing the pinion may not be a good idea. But I am trying to learn more about SAAB trannies.

Thanks for your input.

pierre

ps I went to SAAB dealer here in AK and they have listed the pinion/ring gear as NLA, part number 8715765. At least for 1988 models. I'll check on the 94 vert today.

[Geoff]

they need to be replaced as a matched set - which involves tearing the box down. Otherwise it will grenade in a few thousand miles.
The early 5spds had the 33 tooth ring gear and '89+ 5spds had a 35 tooth ring gear.

[DeLorean]

they need to be replaced as a matched set - which involves tearing the box down. Otherwise it will grenade in a few thousand miles.
The early 5spds had the 33 tooth ring gear and '89+ 5spds had a 35 tooth ring gear.

The warranty replacement E.I. trans I got didn't have a matched set... it lasted about an an engine oil change before the pinion gear lost a tooth and then failed alltogether so that's probably accurate! Also if the ring and pinion are not matched, get ready to hear a "WaaaaaaaaaaaaaRRRRrrrrrrrrr noise everywhere you go

[idiot_saabvant]

Thanks Geoff,

I'll keep with a matched set. Now I just have to find a second unit I can nab the ring/pinion gear from. I've located a four speed from a '78 99 in good shape, but do not know if it would fit my 88 block. Plus I understand they are (may) have a geared primary drive and not a chained one. So do not know if the primary drives are interchangeable. Thanks again for your input.

ps

[Geoff]

The '78 should have the chain primary. The R&P would be 9:35 vs. 9:33 for your '88 (so long as its really an '88 gearbox). I don't know if you can put the 4spd R&P in or not.

[Nate]

Wouldn't the end of the 4 speed pinion shaft be different since there isn't a 5th gear hanging off the end of it.

[matt]

I'm sure Luke could tell us from memory if there's a difference and how much it is. But he's in Hawaii soaking up the sun and surf. Lucky Bastard.

[Geoff]

I want to go to Hawaii, yay!


Now back to your regularly scheduled nonsense

[idiot_saabvant]

Thanks for the input.

I was able to source a steel pinion bearing housing from 99 4spd and found a '81 pinion and ring gear set. I'll put the steel pinion bearing on a newly re-bearinged 81 pinion shaft. I'll machine the 81 pinion shaft end (with shims and snap ring) to be threaded (circa 88 pinion shaft). I'll be able to rebuild a new tranny as I was able to pick up a chillcast housing http://www.saabphotos.com/gallery/album571/saabtr6 .

I also learned that one can reuse 1/4 syncros for 2/3 syncros and one can reuse the lay shafts when scalling has worn through the chrome. Just turn around and grind in a new groove with a thin cutting disk. This person also likes his backlash tight. Say 0.003 to 0.005. So I got a couple of weeks worth of taking apart my 88 5spd and putting the guts into my new found 4spd tranny case.

I would think chillcast housing, steel pinion bearing housing and Luke's steel diff cover should make for a stronger tranny set up.

ps