95 3.4 dohc to 97 3.4 dohc is it possible
 

can i put a 95 3.4 dohc in a 97 monte carlo which also has a 3.4 dohc the problem is on the 97 it has a oil leak in the rear of the engine and i dont know for sure where its coming from i do know that the 97 has the 4t65e transmission and the 95 has the 4t60e is there anyway to switch the motors and if so will i have to change anything i bleive gm switched the systems from obdI TO obdII in 97 so i dont know if i can change them :(

I really wish i could help here...good question. I would think you would need ALL the wiring changed too, to support OBDII. Also I think the 4T60 uses the same bolt pattern as the 4T65, so that SHOULD bolt up. Then again, can you just replace the engine and trans? Because IDK if the 4T60 would work with OBDII set up.

There are other members that would know more on this, hopefully they will chime in soon.

if you can get the wire harness and the trans imo should be the best rout to go before you put it in replace all of the gaskets and put in some goodies for that engine. ;P but with the engine you have it should be a simple fix to doi think it is one of the valve gaskets leaking or where the oil sending unit is doing it. i will check those before the swap. if you allready got the power train replace every thing as in gasket wise and put in new pugs while the engine is out of the car.

Before you swap to an older, less powerful and less efficient LQ1, try and diagnose the oil leak. Is it coming from the back as in the back of the engine compartment or the back of the engine itself? A common oil leak is the oil pump drive o ring. It sits at the back of the engine itself, slightly under the right bank head. To replace it, you will need to remove the UIM, LIM, and right head, remove the drive and replace the o-ring. It would be far less work than swapping engines and while you are at it you could so the head gaskets, LIM/UIM gaskets and timing belt. When you are done you will have a nice freshened up engine with no leaks, proper timing and will run 100% better. Plus you will still have OBDII and the 5 extra hp/tq and a more rev happy engine than the 95 version.

Yeah, you'd have to convert to OBDI. That's a lot of work to put into something that's older, less efficient. Now if that's all you got and you can't get another motor, then it can be done, it's just a PITA.

i think he is thinking to go to the newer 97 3.4 dual cam engine mrl compared to his older 3.4 obd I engine. but the two engines imo is a good engine's

Thats not the way I read it. He asks if he can put a 95 engine into a 97 monte carlo. Unless he worded it incorrectly in his post, then Im pretty sure thats what he is asking.