Why could my transmissions keep blowing?

[Grey Vw]

Something is definitely not right with my car. My first transmission lasted me a year and died by diff pin.

The other three trannies have died by spider gears and the latest one broke in two minutes. It was the best shifting tranny I ever had. The side spider gears didn't break, it was a top or bottom one. I tried starting it again and got a big hole in the case. I beat on them but know other people beat on them even more without breakage.

Fastivab6t said the diff bearings were bad when he reset the spider gears and welded the diff pin. Could this have made the diff bounce around?

I've had the same mounts always except the rear one has been solid after the first tranny since it ripped apart.

It didn't matter if they had gear oil or atf, street tires or drag radials. Is there something wrong or is this a chain of bad trannies?

Whatever it is I will fix it, this car is just too fun.

[Nerd Racing]

how straight are your axles?

[Grey Vw]

The driver side axle was brand new and the intermediate shaft and passenger are O.E.M. I have another passenger axle I could try.

How would I check for straightness?

[htchbck]

I think Nerd's talking about the angle relative to the trans?

[Christ]

I'd be inclined to think it's just a rash of bad ones... or ones that others beat on before you got them.

Excessive drive line angle can torque on the gears and bearings pretty hard... your axles should be just slightly off level (like an inch difference between diff centerline and hub centerline). If they're completely straight, you get vibration, which is wholly another problem.

[M3NTAL]

When you grabbed your other trannys you kept at least 1 axle or half shaft in the trans while transporting right?

I put zip ties through where the axle shafts go to keep the spider gears from flopping around

[Damkid]

^^Once the trans is installed, the spider gears would be in the right spot lol

If you mounts are off, it could potentially cause sideways stress on the diff possibly causing your issues.... considering you had the drivers axle pop out, i'd guess this is the case and that your motor/trans is too far to the pass. side.... this is just my guess though

[Christ]

^^^ That is why you measure CV shafts in the "relaxed" position. If they're compressed too far, they tend to want to "walk" the shaft away from the CV, putting pressure on the diff side gears and the oil seal.

[Rocketman]

I wonder if the solid mount is stressing something that would normally need a little give or flex?

I know the Probe guys used to make what was called a "Tranny Saver" it was a thick plate that bolted around the intermediate shaft portion of the diff, using one of the mount bolts. Kept things from flexing

Flex though, wouldn't have much to do with what happens inside the diff like you're experiencing

Just some thoughts

[Grey Vw]

I'll be making new mounts soon for the hydro tranny swap and hope for the best. The only reason I really want to fix it again is cause I got a green ebay short shifter and really want to try it. I already scouted out my next victim (tranny).

^^Once the trans is installed, the spider gears would be in the right spot lol

If you mounts are off, it could potentially cause sideways stress on the diff possibly causing your issues.... considering you had the drivers axle pop out, i'd guess this is the case and that your motor/trans is too far to the pass. side.... this is just my guess though

My motor is actually a too close to the drivers side. I found out why the axle popped out. When I pulled the tranny the intermediate shaft came with it and I didn't connect axle and shaft properly.

I beat the living ____ out of the old tranny trying to get the driver axle cup out. It was welded in. I could see the c-clip and even tried beating the axle out from inside the diff.

[Movin]

Looked like all your failures are cross shaft and spider related? Set it up tighter to
eliminate free play. You are already welding gears? A locker would stop one tire
burn offs with out weakening the metal in critical areas. As often as you are into
the trans maybe jb welding a good inner cv to the side gear spines would take the click
out enough so it would live. What you really need is a spool and be done with it.
Just opinionatin outside the box a little, you might find something to try!!

[Damkid]

With my setup and how I have to swap differentials to make my swap work, anytime I'm looking at changing a tranny or any tranny issue, I always have to open up the tranny to make repairs or harvest the diff or anything salvageable that I maybe able to use in the next tranny..... Doing that really gives me an idea as to what caused the break downs and what I can do to prevent the next breakdown..... Since I have an Mfactory installed now, I don't have to worry about the spider gears flying through the case anymore :lol:

[Movin]

^^^ there ya go, something with a good track record! Not that Dam kid would be abusive
or anything but I would have to assume it is well tested!

[Damkid]

Lol oh I test my tranny very well haha

[nitrofarm]

Do you guys think its possible his tranny/motor is mounted to far to on side? If he had an axle pop out.Maybe the opposite side is bound up a little.Causing the axle to push in towards the diff? I'm assuming he made custom mounts,because he said he made a custom tranny cross member.
edit just realized Damkid said the exact same thing