Swapping a FWD trans... Is it that hard??

I've got a 2005 Mazda MPV, and the trans is shot. Repair costs were prohibitive, so I picked up a low mileage used trans.

My plan was to pay a local mechanic to swap, but then I found all the local shops seem to be afraid of it. What's up with that? I guess I shouldn't be surprised, some of them are scared to work on anything that doesn't have a carbeuater.

Ok, so I'll do it myself. I've got a complete shop including a lift and a hoist. The only thing I'm short of is time. What could go wrong?

But then I remembered- I've actually never swapped a FWD auto. I've done RWD, and I've swapped FWD engine/ trans combos, but I've never installed a FWD trans, nor cracked one open.

No problem. There is always YouTube.

Believe it or not, there seem to be painfully few YouTube videos on FWD trans installs.

So help me out. Is it really that hard? Is it more involved than pull out the old, stick in the new, a few new gaskets, and topping it off with fluid? Am I kidding myself?

The last thing I need is convert my perfectly good minivan into a pile of scrap parts. And don't get any ideas about the Soccer Mom Challenge!

Depends upon the vehicle.

I've done approx 6 FWD swaps and 10-15 AWD Transmission swaps. It really depends on the vehicle. If it is a 4 cylinder it should be a piece of cake. 6 cylinders make the space much tighter and can turn the job into a real bear.

The quarter shafts can sometimes be a pain to pull, There may be subframe supports you need to remove, and sometimes removal of the transmission from the engine can be a pain because you need to lift/drop the engine some to clear cross/frame members, but otherwise it is very similar to a RWD swap.

In reply to NordicSaab:

Not concerned about physical space or mechanical issues.

More concerned with fluids and clutches, alignment, torque converter issues, etc.

The MPVs are 6 cyl.

SVreX wrote: In reply to NordicSaab: Not concerned about physical space or mechanical issues. More concerned with fluids and clutches, alignment, torque converter issues, etc. The MPVs are 6 cyl.

IMO, These are all basically the same as a RWD swap.

Not too tough if you have a lift. Maybe ask one of the shops that declined the job to print you the instructions off Mitchell or alldata.

You will have to support the engine. This is the important part, as I prefer to avoid death or serious injuries.This is done from the top. Harbor Freight sells a fixture to do this, or you can use pipe or some 4x4 boards across the top of the engine bay and chain, bolts or heavy wire for the engine to hang from. You do this because you need to remove the front subframe and you don't want the engine and trans falling out on you. Special attention should be paid to the flywheel end of the engine. The balancer end is probably mounted to the body, but the flywheel end is supported by the trans.

Once everything is supported the axle shafts will need to come out, remove whatever exhaust is in the way, drop the front subframe, and after that it's the same as a rwd trans. Lines, wires, shifter, torque converter bolts, bellhousing bolts, and probably a few support brackets between the engine and trans. Now this job will be just about impossible without a high lift tranny Jack and a competent helper. You really only need the helper for the part of physically removing and installing the trans and also the subframe.

Is that trans related to what Ford was using at the same time? Ford had problems in that era with stripping the splines out of the converter. If it is make sure you install a new torque converter. Also don't forget your rear main seal while you're in there.

EDIT; Harbor Freight support bar

http://m.harborfreight.com/catalogsearch/result?q=engine+support

In reply to gearheadmb:

Thx.

I think I can get by without a high lift tranny jack. What I usually do for stuff like this is put the trans on the floor, lower the car over it, get it close (strap it, or bolt it), then lift them together. I have manual screw type high lift safety stands I can use for final adjustments if I need them.

I got a torque converter with the trans, but I will check the splines. And, thanks for the reminder on the rear seal.

If you have a hoist, low tranny jack, and the above mentioned competent helper, it may be easier to pull the engine/trans as one unit. It for damnsure will be far easier to remove/install the tranny from the engine and do the seals with the whole thing out, where you will have infinite space to reach everything. Especially the converter nuts; I cannot describe how much I despise doing the converter nuts with the assembly in the car.

Things to replace or you'll be sorry you didn't: converter seal, axle seals, rear main seal, ALL of the old fluid in the salvage tranny (and throw in a bottle of Lube Gard).

Things to consider replacing because you have room to reach them with the whole thing out: engine and tranny mounts (you'll be surprised how much less NVH there will be with new mounts), fuel filter, water pump/timing belt, any vacuum hose and plastic bits that are looking/feeling old, starter (if it is the OEM unit and has more then 100K miles, and keep the old one as a backup), new CV axles, steering rack bushings, front sway bar bushings.

Rock Auto is your friend.

I did all of this in about 15 hours without a helper (sucked, and really slowed down progress at times) or lift, on my Escort about 1-1/2 years ago, in my driveway. Which means YOU CAN DOEEEET!!!

Never done an FWD auto, but the focus SVT was relatively easy. axles, exhaust, support engine from top, mounts, wires, shifter, etc (like others have said) then it is ready to go.

The 6 speed SVT trans was right at the limit of what I could lay on my back and benchpress, so I was able to r&r without the aid of a friend or a jack (but it was sketchy - would not recommend). MPV is probably heavier too.

I'd say you should be able to do it no problem.

FWD transmissions are not tough, but I'd say that the MPV is tougher than average. Lots of bolts and braces that are not easy to access. I tried to pull one for parts at a Pick N Pull yard. I needed a couple internal parts to fix mine, and figured I'd grab the whole thing since it was cheap (1/2 price day.) I gave up about half way through, and just removed the end case to get what I needed. To be fair, it was not easy to access sitting on rims in a junkyard and I was short on time, but I ran into a lot more obstacles than I was expecting. Especially for a junk yard pull which is usually quick and dirty, with no care about putting it back together.

That said, if you are considering the swap yourself, I strongly recommend taking a hard look at the fix I recommended in your other thread. I'd much rather attempt the fix than the swap, it's a lot less effort and time. The MPV transmissions usually go bad because of a factory part flaw. One of the pistons develops a crack, allowing reverse to drag with the higher gears engaged, wearing out the 3-5 and reverse frictions. If your van drives in first and second but slips after the 2-3 shift, that is the likely cause. Reverse usually goes out too. A swapped used tranny will still have the defective part. It could last a long time, or go out soon. The replacement part doesn't crack. Opening up the transmission sounds scary, but you are not going very deep into it. It's pretty much take parts out, replace the bad with new, put back in the same order. When I fixed mine, it was the first time I did anything with an auto.

In reply to Boost_Crazy:

Thanks, I still may try the fix you shared. But this is not a 2-3 slip, it slips at all time under load, most often in 1. Plus, it leaks from everywhere, and the burned clutches smell is really obvious at all times.

So, as much as I want to believe in your suggestion, I'm not feeling it.

Having assisted in one FWD transmission swap and having limited tools/space I would pull the engine and trans then do the swap. It makes putting the engine and trans back together so much easier.

When we put FWD cars together on the assembly line, the engine and gearbox go in as one unit. If there's a subframe, it all goes in as a unit. Why not do it that way?

My chumpcar team replaced the clutch in the '97 626 so if the MPV uses a similar 2.5 V-6 I'd say it would have to be easier to pull the whole thing and R&R the trans with it outside the car.

This might even be a good time to do a 5 speed swap if it is the same motor

In reply to Boost_Crazy:

In reply to Boost_Crazy: Thanks, I still may try the fix you shared. But this is not a 2-3 slip, it slips at all time under load, most often in 1. Plus, it leaks from everywhere, and the burned clutches smell is really obvious at all times. So, as much as I want to believe in your suggestion, I'm not feeling it.

That does sound like something different, the problem I described shouldn't affect first or second gear.

The swap shouldn't be too bad. It's just a lot of stuff in the way, mostly sub frame if I remember correctly. Just give yourself time, and label parts as you remove them.

Biggest problem with FWD transmissions is having enough space between the frame rails to move the transmission back and drop it out. Sometimes you have to tilt the engine to get clearance to pull it back.

Have helped on several Focuses and the biggest problem is getting the trans wiggled in position to slide on the motor. Much easier when the whole thing is pulled as an assembly.

The FSM should describe the procedure pretty accurately. The Mazda FSMs are very good from my experience.

Another vote for dropping the subframe. If you have a hoist, its the way to go.

Just unhook everything, loosen the subframe bolts, set the car back down (land the subframe on some blocks or 4 jack stands) take out bolts and lift car away.

Hal wrote: Have helped on several Focuses and the biggest problem is getting the trans wiggled in position to slide on the motor. Much easier when the whole thing is pulled as an assembly.

That was by far the worst part of my SVT Focus clutch install. Getting the transmission aligned just so was a huge time sink.

I worked in a transmission shop for 2 years. I never pulled an engine. All the suggestions of pulling engines are by people who have not done enough transmission swaps to get comfortable with them.

There could be all sorts of minor hangups to the job, but most of them will hinge on tools available (wobble sockets, long extensions, etc) and technique (separating ball joints, axles, etc) and not so much on whether this car or that car is particularly 'hard'. They're all particularly hard when they're your first one ever.

The only one i remember being particularly tricky was northstar cadillacs because of all the careful tilting involved to get it in and out. Even then, it's not like i dreaded going to work if i had one to do. The transmission that pissed me off the worst ever was an early 90's 4wd dakota that had a factory crossmember that REALLY SHOULD have been made to bolt in and out rather than be welded right in god damn way of everything. And that's a RWD-style unit! Nothing fwd ever pissed me off as bad as that.

No, I've done several transmission swaps in FWD Chrysler vehicles. After a couple, I realized that it was a little longer (like a couple of hours) to drop the entire engine and transaxle as an assembly.

This also allowed me to replace any bad seals, replace the starter or verify the starter heat shield was in place, replace power steering lines, turbo lines, etc.

To each his own, but the guys that get paid flat rate leave the engine in the car.

No, I've done several transmission swaps in FWD Chrysler vehicles. After a couple, I realized that it was a little longer (like a couple of hours) to drop the entire engine and transaxle as an assembly.

FWD chryslers are unusually easy to drop the whole drivetrain out of. Not having a full subframe helps. I didn't drop the engine out of my Intrepid when i did that one, and the hardest part of the whole thing was a water pipe that bracketed to the upper bellhousing bolts. There are certain cars where not stabbing the dipstick tube into the trans at the right time can add tons of labor. It's little stuff that gets you, not FWD vs RWD.

To each his own, but the guys that get paid flat rate leave the engine in the car.

Thank you.

Some FWD transmissions are simple. My easiest was a FWD turbo 1G Eclipse. I was used to doing AWD's which are a tight fit and heavy. The FWD unit took about an hour total, broken one out and the replacement in.