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Engine Swap: Legacy L into Forester S

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My father has a 2001 Forester S with a bad head gasket. It also has a bad transmission. My wife just rolled my 2001 Subaru Legacy L and totaled the car.  :(  Is it possible (or how hard would it be) to swap the legacy engine and transmission into the Forester body? They are both automatics but the forester has a straight transmission lever throw where the Legacy has the sideways throws to keep you out of reverse and 1/2. Here are some numbers because more information is better.


Legacy Engine number EJ251AXAWL
Forester Engine Number EJ251AXVAB

Legacy Trans Number TZ1A4ZCCCA
Forester Trans Number TZ1A3ZC3AA

My father and I are both pretty handy with this stuff and I've watched the online videos and it doesn't look like anything we can't tackle. I mainly want to know if it's possible and if it's a straight swap over.

Thanks for any and all help that may be out there.

~Jeffrey R.

yes.  will work, but a few notes

 

Keep the current Forrester intake manifold and bolt it onto the Legacy engine.

 

You will also need to swap out the rear diff and transmission computer as the gear ratios are different.

 

Keep in mind the car may feel a little slower off the line with the taller 4.11 Legacy gearing vs. the 4.44 Forester.  But you may get slightly better highway mileage due to the dropped cruising speed RPMs.

Yep keep Forester intake and swap legacy rear diff with trans.

 

There are two crank/cam pulley variations on those years. If they’re different you have to use the Forester drivers side cam pulley and crank sprocket in the legacy engine (you keep those sprockets matched with the ECU is how I view it). But they’re interchangeable so just swap them out. Good time to install a complete timing kit anyway. Belt pulleys and tensioner.

 

Gloyale may not have mentioned it because he knows they’re already the same, I’m not 100% certain which models got which style though it may be an auto-manual thing...

 

But yeah, easy swap.

  • Author

Thanks for the info. Is it possible to remove both the transmission and the engine while they are still connected? Is there enough room for that?

 

~Jeffrey R.

Thanks for the info. Is it possible to remove both the transmission and the engine while they are still connected? Is there enough room for that?

 

~Jeffrey R.

 

yeah but it's a pain.  May not even be possible with teh Legacy not having a body spacer, the corssmember is too close.

 

Even if it works, You end up dumping oall the fluid out the back.  and then you've got a 600+ lb assembly to manuaver rather than 2 separate 300 lb ones.

 

I would definitely pull one at a time and take the opportunity to reseal the rear of the engine while they are seperated.

  • Author

Thanks again for the info.

 

~Jeffrey R.

Even if it works, You end up dumping oall the fluid out the back.  and then you've got a 600+ lb assembly to manuaver rather than 2 separate 300 lb ones.

Those transmissions weigh 300 freakin pounds? good god

Thanks for the info. Is it possible to remove both the transmission and the engine while they are still connected? Is there enough room for that?

 

~Jeffrey R.

I think it’s easy, fluid does go everywhere and you need a steep angle and vertical space to get the lump out nearly vertical. I’ve done it on old gen, new gen, 4 and 6 cylinder automatics, but I think all the new gen I’ve done were outbacks and a 99 SUS which has body spacers, although seems to me they’ve never been right or hard to get out, they pull right out. if I had a non lifted Subaru it wouldn’t have occurred to me it wasn’t possible, never seemed hard or lacking space but ive never tried it on those either.

 

there’s no additional time constraint and you gain easier access to torque converter and bellhousing bolts and separating the engine and trans insitu which I don’t find always goes easy and smoothly. Rusty lower nuts, granted there’s only two but chiseling and/or welding those things off is an annoyance for me, I don’t have a full on professional shop with torches and welders easily accessed at all times particularly in the winter.

  • 2 weeks later...
  • Author

Thank you for all the help. Decided not to do the transmission for the moment. Back on the road again. :D 26730907_10214796154594825_8468864756854

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