So I found an 04 wrx transmission with a blown 3rd gear, and I've found a good source for a new gear. I've been told that at a mechanic, that's like 10+hours of work to rebuild/ repair it. can I maybe....do this myself? is it REALLY complicated? Should I just find another transmission?

 

Oh, btw, I'm no mechanic, just a guy with a car xD

Edited August 22, 201213 yr by natext6

Do you own a press and a bearing splitter?

 

Factory repair manual?

 

Can you remove and install the transmission/clutch?

No, no, and the trans is already out, I'll be putting it in with an engine swap (if i can make this happen)

 

I could easily get a factory manual tho.

3rd and 4th are a pair that have to be replaced together. Both drive and driven.

 

There will have been a TON of metal that has gone into everything - figure on replacing every major bearing, all the syncro's, and reshimming the ring and pinion. There will be at least $600 in parts above and beyond the gears.

 

You will need a press with a wide enough through-hole in the bed to pass the driven gear for 1st.

 

You will need an accurate dial indicator and a good solid method of attaching it to set the ring and pinion lash and setting the contact of the teeth involves "reading" the Prussian blue or white/red lead contact patches....

 

If you aren't a mechanic and you don't have the tools or skills to attempt this I wouldn't do it at all. The first one I did was for a friend and went into a race vehicle where longevity was a bonus not a requirement. I have done more of them since and have learned something each time. If you want a reliable transmission then your best bet is a used one. It will be cheaper and with your inexperience it will probably last longer.

 

GD

Hahaha, looks like this is way beyond my reach:-p for now!

3rd and 4th are a pair that have to be replaced together. Both drive and driven.

 

There will have been a TON of metal that has gone into everything - figure on replacing every major bearing, all the syncro's, and reshimming the ring and pinion. There will be at least $600 in parts above and beyond the gears.

 

You will need a press with a wide enough through-hole in the bed to pass the driven gear for 1st.

 

You will need an accurate dial indicator and a good solid method of attaching it to set the ring and pinion lash and setting the contact of the teeth involves "reading" the Prussian blue or white/red lead contact patches....

 

If you aren't a mechanic and you don't have the tools or skills to attempt this I wouldn't do it at all. The first one I did was for a friend and went into a race vehicle where longevity was a bonus not a requirement. I have done more of them since and have learned something each time. If you want a reliable transmission then your best bet is a used one. It will be cheaper and with your inexperience it will probably last longer.

 

GD

 

Pretty much what GD said. Not for the faint of heart. Rebuilding engines is way easier.

Like GD said, Any time a gear is replaced it has to be done as a set, except 1 2 and reverse since those are formed into the mainshaft. One of those goes out you replace the entire mainshaft, along with the gear set on the countershaft.

Replacing ANY gear on the countershaft (the lower shaft) means disassembling the pinion shaft so the bearings can be pressed off. Then when re-installed you need new crush washers for the thrust bearings on the pinion shaft, and you need to reset pinion depth and ring gear backlash.

Basically it is WAY more work than it's worth to rebuild one of these, and some of the parts are astronomically expensive. You'll spend more on a rebuild than you will to go get a used working trans.

 

There are some parts you could keep. Center diff and transfer gears and if the front diff is limited slip keep that.

I haven't purchased anything yet. Would the center lsd and such be worth 300$?

A DCCD maybe if it comes with the module and wiring.

Standard VLSD center diff you can get from any soob AWD trans back to 1990. Although I probably shouldn't say that. Somewhere along the line there was a change in the way they worked internally. The older center diffs you could disassemble and replace just the viscous coupling if it went bad. Newer ones you just have to replace the whole thing. I'm not sure if the the newer gen center diffs are the same spline count and physical size as the older ones. Someone does?

Either way, standard VLSD isn't worth any $300. Get them at the U-pull yard for under $50.