Installed new 43 tooth driven gear and a 17 tooth drive gear per calculations and rec. from the shop down in Louisiana.

The gear seemed to spin fine before I installed the transmission in car. After a couple runs speedo stopped working, went through the systematic test, removed gauge cluster, checked speedometer with drill, removed speedo cable, removed tail shaft, and found the driven gear broke in to two pieces (see pics).

The old driven gear was the type that slipped over a metal shaft, the new one that PATC sent was the one piece plastic gear with plastic shaft. They said they did send the correct housing for the large gear (43 teeth/purple) I found that the drive gear (17 teeth/red) was still clipped in fine on the output shaft. I'm just wondering what caused the gear to snap.

Car runs great, I love the full manual transgo kit w/the quicksilver shifter, nice combo. I just need the speedo though so I can pass inspection, what ever it takes. I don't want to to just throw in another gear and have it snap right away. Does it matter what side of the drive gear goes towards the front of the transmission for proper meshing? In the pictures, the one side that has black marks is the side with marker on it, showing that it was facing the front of the transmission when I removed it from the output shaft.

I should mention, PATC did send a new o ring that I asked for, but no small seal, is there supposed to be a seal and o ring on the driven gear shaft inside the housing? Can see the seal I am talking about 6 sections down with the clips and o rings at the site linked below.

Thank you!!!

http://www.transmissioncenter.net/sp...n_______va.htm

 

On the 700R4 there are two locations on the output shaft for the drive gear. If the wrong location was used it puts excessive pressure on the driven gear. I can't recall exactly which location is supposed to be used. BUt I think the one for the f-body's is the mounting point furthest from the driven gear.

RBob.

 

I'll have to check my output shaft, it is a th350, thought there was only one hole but will check for sure.

 

OK, didn't realize it was a TH350. It probably only has the one mounting hole location.

Try turning /rotating the speedometer cable from the tranny end. Maybe it is binding. Should be able to turn it by hand.

RBob.

 

Installed the new driven gear last night, same 43 teeth, same style one piece/plastic shaft and installed the gauge cluster this morning, the cable does now spin pretty easy in the sheath now, was a bit tighter without greasing. I lubed it with the Green Grease, great stuff and I didn't have any graphite lube.

Car is on solid jack stands and ran it through the gears and speedo seems to be working so far, no odd sounds. I'm hoping it was just a fluke thing, but I have a feeling my B&M shift cable was pushing into the speedo cable and may have put pressure on the driven gear causing the first one to snap.

Thank you for the replys!