2003 Auto to Manual swap

I’ve been running with the auto ECU for several weeks now, no issues other than the 5 or so codes related to the auto trans that will pop up. They don’t affect the performance or drivability at all.

 

Ok thanks. Once I get my JBA Y-pipe straightened out (and my wiring all sorted) I’d like to start the truck even if I don’t have my manual ECM yet.

 

Got my driveshaft apart this morning for new carrier bearing. I followed the old post from @TacomaJPP. Took a bit of “effort” to get the two shafts separated. .

 

Picked up my new carrier bearing and manual ECM yesterday. Carrier bearing is straightforward but would it be better to get the truck running again before swapping in the new ECM? I know @drr said he was running his manual conversion with the computer from the automatic. I thought I would just focus on getting everything sorted mechanically and then swap out the ECM. Thoughts?


Also, right now the biggest obstacle for me is the exhaust. Specifically the Y-pipe for my ‘new to me’ JBA headers. Both bolts snapped when I was removing the old A/F sensor and my friend is going to help me drill them out. This Y-pipe has no flange on it, and I think most folks just weld the front cat to the Y-pipe, but if I took it to an exhaust shop, do you think they could weld a flange on it while it was out of the truck, and then when it’s time to install the exhaust I could just shorten the straight pipe a bit? This is just my exhaust pushed up against the y-pipe. You can also see my broken bolts that need to be drilled out.

 

Weekend update. I got my manual ECM installed and all my clutch wiring installed. I filled the clutch m/c with fluid, but didn’t bleed it yet. I also found all my battery cables/alternator wires wrapped up in loons and installed. The transmission crossmember and HD trans mount are all torques to spec. I cleaned up my y-pipe, tightened up the headers, and did a trial fit of the exhaust. I think I didn’t leave enough metal on the front of my cat, but my buddy thinks we can fill the gap with weld.

 

Is there any special trick for installing the shifter and rotating the ‘locking’ groove?

 

Weekend update:

• got all the clutch/cruise wiring connected.
• shifters installed. I mistakenly installed the t/c shifter from the automatic and couldn’t figure out why my shifter knob was backwards Doh!
• Power steering pressure switch finally came so was able to reassemble everything up top
• Big 7 (actually Big 4) battery cables

I was able to start the truck and it fired right up (with clutch pedal depressed). I tried starting it with clutch in ‘released’ position, and it wouldn’t start, so I know the neutral safety switch is wired properly.

The remaining items are:

• Bleed clutch
• Install front/rear driveshafts
• Weld catalytic converter to header

 

Regarding the cat welding, there is a 70 mm gap between the cat and the header y-pipe (why didn’t they just make the y-pipe with a flange!). I’m a hack welder at best but I don’t think that gap can be bridged. I was thinking of trying to cut a small band of exhaust pipe and use that as filler? Do you think that would work?


I was thinking of getting a slice out this pipe and using that as filler:

 

The two surfaces need to be flat and parallel to each other. Looks like there’s gap in some places and interference in others. Now would be the ideal time to put flanges on, they will take up the gap after you straighten those cuts out and allow you to weld each side separately and then bolt it together.



https://www.summitracing.com/parts/sum-626013

Something like this.

 

Here’s what I was thinking

 

oh. Ok. I didn’t see your response until I posted. That works too! Let me do some measuring for diameter

 

Another option is run stringer beads on both sides till they meet in the middle . what we did in the field on poor fit up joints.

I would not try adding another piece if going that route get a piece that fits inside both ID`s weld that in place .

Flanges should be easy to find new I bought new ones from walker exhaust a few years ago.

if you were closer I would be glad to help.

good luck.

 

I got the cat welded in. I did a hack/temp job just enough to get it to my buddy’s shop. I’m going to ask him to cut it off and weld on the flanges I got from Summit.

I bles the clutch using a vacuum ‘gun’ that hooks up to my air compressor I use it for bleeding motorcycle brakes, but I’m not 100% convinced of its benefit. I did a tally back the truck out of the garage, so it definitely can move under its own power. . I started purring the interior back together. I want to fill the back part of the hole in the trans tunnel. Maybe with some foam. Here she is our of the shop

 

Nice dude!! It’s so nice having the 5spd, manual swap was the best thing I ever did to my tacoma! Easier than it seems, right?
almost everything is plug and play, especially if you get the manual ecu to not have the CEL on all the time.
Nice thread and Sick truck!

 

Easier than it seems? I've been following all 5MT swap threads because I want to do it to my 04 DC. This thread is 11 pages long and started in February, lol.

Oserhagen's walk through is awesome too... but it doesn't seem that easy to me and my DIYer skill level.

 

I did the swap myself a couple years ago in my 01 double cab, I have a thread on it, I don’t think I finished the thread but after getting the parts it took me a weekend to complete the swap.
If you get all the parts and you are capable of doing stuff yourself it is pretty easy actually. The only wiring is for the clutch start switch and reverse light indicator which is only like 4-5 wires if I remember correctly. And there is a very simple wiring diagram floating around on TW somewhere, I think I posted it in my thread if not I’ll see if I have the screenshot still and post it here. And Unless you feel the need to wire the clutch cancel start switch so you can start the truck without pressing in the clutch, that’s it, I chose not to and don’t see a need for it. And the only other thing you have to do that isn’t factory plug and play is drilling out the holes to install the master cylinder for the clutch. Which the spot is there for it in the firewall, a few measurements to get it centered and it isn’t that hard to get it right. Everything else is plug and play. Keep in mind toyota made the same engine and trans configuration in other models so it’s not like you would have to retro fit anything.
This is coming from a diy guy that has no mechanic background other than my own garage and learning stuff from doing it myself.
If you’ve got any question feel free to ask, I’d be happy to help, it’s well worth it doing the swap!!!

Also let me add, I did buy a donor truck for the swap so I’m sure that made it easier but I still bought all new parts other than the transmission itself. And it does depend on your tacoma, I have seen others having to adjust their trans mount cross member but I think that is from guys going from 2wd to 4wd. It has been a while since I’ve looked at all these threads, and maybe easy wasn’t the right word but let me just say that I spent 8 months from the time I bought the donor to when I did the swap researching and being very intimidated by it but once I started I wished I would’ve done it sooner because it wasn’t as hard as it seemed reading through the threads

 

To be honest, the actual auto-to-manual swap wasn’t that bad. I think if I had a donor truck it would’ve helped speed things along but I wasn’t in any rush. I also did a lot of other work along the way (ball joints, lower control arm bushings, alignment kit, power steering lines, POR15 front parts of frame, etc.) and for me some of these were the first time I ever did them (eg, ball joints and control arm bushings) which required special tools that I had to order/buy/assemble. I had to wait 2 weeks for my Sunex 2-stage trans Jack to arrive. Granted, I could’ve taken the trans out with just a floor jack or a HF trans jack, but since I have a 2-post lift in my shop, it just made sense for me to invest in a good trans jack. You guys probably don’t know this, but I’m semi-paralyzed in my right arm from a motorcycle accident back in 2008 (brachial plexus injury) so I also have to work a little differently.

I absolutely could not have done this without the help from everyone on this forum! I never felt like an idiot (well, not too much) asking dumb questions and always got great feedback!

Today’s goal is to get interior back together and start plotting out how to fill the back part of the hole in the trans tunnel. I’ll send a pic later to show what I’m talking about.

just out of curiosity, can I still get a new OEM carpet for this truck? I know removing the seats will snap every bolt (NJ rust) but I was thinking a new carpet might be nice.

 

Agree 100%. Having access to the diagrams and other threads definitely made it mess daunting. For me, reading all of @SafetyDang and the spin-off threads were what gave me the final ‘courage’ to jump in the deep end. lol

To be honest, the most intimidating part of the project had nothing to do with the actual trans swap. It was putting on the headers and having to weld the cat together. I’ve only welded like three times, and I know I didn’t do a great job, but it should be good enough so I can take it to my buddy’s shop and have him weld it up better.

 

I believe OEM carpet isn’t available anymore (double check with research). But there are a couple of great aftermarket choices.

It’s been about 15 years ago but there was a place out of Utah that everyone here promoted for new interior carpet.

When I get on my computer I can see if I still have a link (and if they’re still around).

 

“a diy guy that has no mechanic background other than my own garage and learning stuff from doing it myself.”

This describes me to a “t”. I also k kw my limits of comfort and skill and will gladly bring my trucks to my buddy’s shop for work.

If I had someone local that would help me do the swap, I’d do it in a heartbeat.

Let me ask you a question about the “donor truck” part. If I gathered the tranny, transfer case, drive shafts, ECU, master and slave cylinders, clutch, clutch/brake pedals, etc isn’t that enough?

Or were there bits and pieces you needed to source all the time? Like hydraulic lines?

One of the main thing that intimidates TF out of me is the wiring. And no, I wouldn’t wire in a clutch start cancel button…never once used it in my 98.

Although if I did the swap I’d probably put one in down the line to make it more OEM.

I appreciate the offer for help. If I grow the balls to do this I’ll reach out.