'96 Mitsubishi 3000GT - Torque Converter Advice

[shima]

Hey guys,

My other ride is as titled. It was my first vehicle, my K5 is my second. I got into wrenching on cars because I moved into a home with a garage and figured I'd try tackling all maintenance stuff on my first car myself. It progressed to the point where I was confident in getting a second vehicle, and that's where I am today.

Anyhow, the torque converter is slowly on its way out in my 3K. It sometimes fails to get into lock-up. By "sometimes", I mean that if I were to drive at highway speeds 5 days in a row, it would likely fail to lock-up on the third or fourth day. So rather seldom overall. When it fails to get into lock-up, the driver doesn't feel it at all. If the CEL didn't come on, I'd have no idea that anything even happened.

I got an excellent transmission guy referral from a fellow CK5 member, and he's taken great care of me. He said he can replace the TC for me and I'll be good to go. But, it's an expensive job.

So after all of that droning, here's my question:

• I'm thinking of driving this thing until I can feel the transmission slipping. With how seldom I drive, I think I can get another 6 months or a year out of it. When I start to feel the trans slipping, I'll have it towed to the shop. If I get to that point, do you all believe that I will have to replace more than just the TC? Will I have done damage to other transmission components?

Thanks for your thoughts, whatever they may be!

 

[76zimmer]

talk with Greg Ducato...a member here, he's the trans expert!

 

[shima]

Decided to just have the job done. Gonna run about $1200, that hurts. But it's not something I am knowledgeable enough or equipped to tackle right now. So it goes I guess!

 

[shima]

@Greg Ducato

I'm a little worried that I am jumping the gun with having the TC replaced. The only diagnosis that I've done is found that the TCU was throwing code 49, "Defective torque converter clutch system".

Could something else aside from the TC cause this issue, and does replacing only the TC make any sense (as opposed to replacing the entire trans)?

Thanks for your thoughts, if you choose to share em!

 

[Smokinthehippies]

No help as my stealth was a 5 speed, but I do miss the little ****er. It was a fun car to flog in the hills. Wished they were rwd

 

[Greg Ducato]

If the converter is bad it should be bad 100 percent of the time. Slippage can be monitored with the correct scan tool by your trans guy or a good technician. That kind of code is very generic and could point to anything in the system from solenoid, to valve body, to converter or wiring. Rather than starting with the most expensive repair I would be looking for the least expensive aspects and go from there. First place to look is a wiring schematic, trace out the TCC wiring and make sure there are no wiring issues or abrasions. If you cant get to the whole wire, overlay the wire from TCM to trans connector and try that. Make sure the brake switch is not out of adjustment as that can cause the converter to drop out of lockup. The valve body on this trans has a tendency to wear the TCC control valve. Sonnax makes a valve kit #41954-03K that will correct this problem and restore integrity to this hydraulic circuit. You can pick up this part and gaskets from your nearest Transtar distributor. While you are in there, I would change out the TCC solenoid since it will never be easier to do.

 

[shima]

If the converter is bad it should be bad 100 percent of the time. Slippage can be monitored with the correct scan tool by your trans guy or a good technician. That kind of code is very generic and could point to anything in the system from solenoid, to valve body, to converter or wiring. Rather than starting with the most expensive repair I would be looking for the least expensive aspects and go from there. First place to look is a wiring schematic, trace out the TCC wiring and make sure there are no wiring issues or abrasions. If you cant get to the whole wire, overlay the wire from TCM to trans connector and try that. Make sure the brake switch is not out of adjustment as that can cause the converter to drop out of lockup. The valve body on this trans has a tendency to wear the TCC control valve. Sonnax makes a valve kit #41954-03K that will correct this problem and restore integrity to this hydraulic circuit. You can pick up this part and gaskets from your nearest Transtar distributor. While you are in there, I would change out the TCC solenoid since it will never be easier to do.

Thanks so much, Greg! I sincerely appreciate you chiming in.

Coincidentally, I called the shop yesterday and told them that I'd like to forego the torque converter replacement. I'm going to wait a bit longer to address this transmission. I'd like to have the time and space to tackle it myself, and also would like to do more research. Your response makes me feel good about that decision. Thanks again.

EDIT: Regarding all of the specific info you provided... you're the man. When I get around to addressing this thing, I'll walk through your post step-by-step and research everything that I don't already understand.

 

[shima]

Greg (or anybody else who knows),

How harmful is it to the transmission when it fails to get into lockup?

I drive this car so rarely (once a month maybe), and feel no slipping when the CEL comes on. I'm wondering if I can get another year or more out of it.

 

[Smokinthehippies]

You're gonna lose mileage and build heat.