1996 Lumina 75K

[Watchingwolf]

I have a 1996 Lumina 3.1L that has suffered a pump failure leading to a torque converter failure in my transmission.

I have located a 3.1L out of a 1998 Monte Carlo with 90K on it that is claimed to be in good condition. I was curious what differences I can expect to encounter and wondering if the swap will work. 

I'll gladly supply any additional info required to get answers.


Thanks!

Nate

[Schurkey]

Are you swapping engines, or transmissions?

[Watchingwolf]

Oh, sorry about that. I need the transmission, however I have located a complete engine cradle with the engine and transmission in place. Everywhere I've read calls out only 1996-1997 as compatible, however if the only issue is a different stall speed or maybe a different gear ratio, I can make that work....What would be the major difference between a 1998 Monte Carlo and a 1996 Lumina?

It appear that it could be a 4T60E or a 4T65E-M15 in a 1998 Monte Carlo but only a 4T60E in a 1996 Lumina. Both would have the 245mm converter.
What other trouble might I run into? I don't have access to the harness from the Monte.

 

[55trucker]

The 65 unlike the 60e does not make use of a vacuum modulator mounted to the side of the casing & the wiring harness plug is also a different design & location.

[Watchingwolf]

Steve~ Thanks for that information! Here is the donor trans ans it does indeed have a vacuum modulator so it would indeed be a 4T60E. ANy other issues I need to watch out for?

 

[55trucker]

Outside of replacing the output shaft seals...nothing mechanical......in situations like these I lean to replacing the trans fluid & filter (at 90,000 miles you don't know the history & how long what's in there has been in there), since the trans has to come off the engine dumping the converter fluid is possible as well (suction gun). You may or may not need to adjust the trans selector switch position after you've got the replacement trans installed.

Edited November 2, 2019 by 55trucker

[Watchingwolf]

Perfect! I actually encountered a snag in the trans swap. My current trans will build pressure and engage at higher rpm. after the car is moving it seems to function as required without slipping, shutter or lurch. The oil is not yet scorched so it is on the rack Monday at a new repair shop who are going to rediagnose, drop the pan and check electrical and pump pressure. It looks like my small town wrench may have got it wrong.

 

[Pontiac6KSTEAWD]

The only other thing he may have to keep in mind is the actual gearing of the tranny may be different. It may not. Its kind of a crap shot unless you know what gearing your old trans had, and what the gearing of this trans is.

[55trucker]

All 60E's will have the same basic gearing, what can change is the sprocket ratio & final drive ratio depending on what engine is in front of the trans. A small torque 3.1 will not have the same final drive as a larger torque 3.8. There's a very good chance that a '96 3100 L82 Lumina & a 98 3100 L82 Monte/Lumina will have the same final drive output.