Built trans?

Well, I finally pulled my trans out of my car after 3 months and I'm pretty sure the center diff is f***ed. I'm making 310 to the wheels right now, but maybe planning to go up to around 420 whp. I've talked to Sheps and they want $1975 for a stage 3 trans. My question is, is that really necessary for the amount of power that I'm making? Is it the best bang for my buck? And will this be sufficient for daily driving as well?

Thanks,
JR

 

[RedTwo]

Keep running stock gearboxes and rebuilding/replacing as they blow? Seems to be the case around these parts. /ubbthreads/images/graemlins/dunno.gif

 

[toybreaker]

A lot of factors determine transmission durablity.

What type of clutch will you be running?

Sprung hub or unsprung?

 

[4thStroke]

I daily my car at 440awhp with a stock transmission with a welded center diff and have done so with pretty good luck.

Our center diffs are weak, either weld it or put a 4 spyder in it. The 4 spider is far more expensive but will drive like stock. Welded centers aren't all that fun to deal with until you launch the car.

 

[DynastyLCD]

^ what he said.

im on a stock transmission, with a welded diff. seems to do just fine. when it breaks, i find what i need to repair it and get it back on the road, call it a day. it holds up pretty well. try to find a late 91/early 92 DSM transmission if you can. they are very strong, and can accept the evo3 gears as well.



it will also make you savvy at transmission repair, if you weren't previously /ubbthreads/images/graemlins/hsugh.gif

 

The trans I just pulled out of the car is a supposedly stock trans with welded diff. I was thinking the welded diff was what broke, but I guess I won't know until I pull it apart.

Does anyone have any other "How To's" on DSM transmission rebuild?

I have this one.
click


And any other specialty tools I'll need beside a shop press?

 

[DynastyLCD]

that's a pretty good write up.

what exactly happened that lead you to believe the center diff is damaged?

 

Here's the way it went down. I took my car to the track, made several very smooth and successful passes with no problems. On the way home I let my friend drive. He completely dumped the clutch at a stop sign at 5k-6k -_- and from there on out the car was immobile. You could still shift the car into every gear, but it would not go anywhere. It would sometimes catch and move for about 20 feet but then seemed to just fall back into a neutral state on it's own. I could also hear what sounded like a very very slight grind at some points. But not much. This is my first DSM and my first manual vehicle so I'm really just learning as I go.

The clutch still looked to have plenty of meat on it, so I'm convinced my problems lie inside the transmission.

 

[turbowop]

Did you try any other gears? It's common to blow up the stock gvr4 first gear.

 

[DynastyLCD]

does it feel this way throughout every gear, as if the clutch was slipping perhaps?

it could also have a non-welded center diff, and have either a broken axle, transfer case, or issues within the viscous coupling. all of these issues would happen with a regular 2-spider differential, as it would simply try to spin the broken axle/tcase/etc (path of least resistance) also, thick silver goo in the transmission oil would indicate a bad viscous coupling.

id say to check your axles, driveshaft, and transfer case for proper operation, if all of these are ok, then go through the transmission. when you get the center differential out, take the top 8 14mm headed bolts out, remove the top of the center differential, and look at the insides. there will either be two spider gears (or 4 if you're really lucky) plus the top and bottom gears, or if it is welded, no spider gears and the top and bottom gears will be welded to the housing.

 

I can shift into every gear and when I release the clutch the car goes no where. What's the easiest way to check my transfer case?

 

[rdomeck]

I'll have to say...Why do people think they can dump the clutch at 5-6K on an all wheel drive car? What stock transmission will hold that? Don't ever let that friend around your car again! And good luck with the trans.

 

[marvinmadman]

Because you can. I've had plenty awd cars and all of them had stock transmissions. They took multiple launches off the studderbox at boost, never had a problem. /ubbthreads/images/graemlins/dunno.gif

 

[OoThomioO]

Heh i'll vouch to Marvinmadman doing that lol...hopefully he'll get the new one on the road and continue to do it -_-

 

[rdomeck]

Quoting marvinmadman:
Because you can. I've had plenty awd cars and all of them had stock transmissions. They took multiple launches off the studderbox at boost, never had a problem. /ubbthreads/images/graemlins/dunno.gif



If you can then this thread would not exist!

 

[mitsuturbo]

Quoting marvinmadman:
Because you can. I've had plenty awd cars and all of them had stock transmissions. They took multiple launches off the studderbox at boost, never had a problem. /ubbthreads/images/graemlins/dunno.gif



I did this as well. I really abused some transmissions, and they actually never broke on the launch.

I can't say the same for 3 bolt rear axles, though.

 

[marvinmadman]

I've never broke any 3 bolt axles either. I'd pull high 1.6x launches all evening at the track. No problems ever except for a weak original clutch slipping. Threw in a used orielly "performance" clutch and continued my assault /ubbthreads/images/graemlins/rofl.gif

 

[mitsuturbo]

I broke something like 13 axles in less than two years. Finally got a 4bolt and didnt break another axle.

 

[marvinmadman]

I never really understood the whole breaking axles ordeal. /ubbthreads/images/graemlins/dunno.gif

 

[donniekak]

I've never broke a trans from a launch either, i have broke several doing 3rd, and 4th gear pulls though.