Hello! I'm currently neck deep in my 5 speed swap and i've come to wiring. A little background info; I have a 99 limited with a 97 5 speed transmission. i have the opportunity to purchase a full 99 sr5 body harness complete with locker harness and i assume the associated modules. i have questions about compatibility, specifically the power seats, sunroof and hvac. i would hate to spend the cash on the harness but only to run into more problems.

im unsure of the direction i need to go. anyone have any advice or ideas?
Thanks in advance!

I have two Sr5's 5 speeds in my driveway now, a 99 and a 00. I had a 99 LTD auto also, trying to remember differences. So the 5 speed SR5 won't have the ETC switch, not needed anyway. My SR5's don't have power seats, but easy enough to grab what you need off the LTD harness. Sunroof and ac should be the same.
I havent done a 5 speed swap, but seems with the 2 harnesses you have everything you need cause wiring can be pieced together.

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Ooh, yeah I forgot the heating/ac control panel different as it LCD, but I think that wiring should be able to be pieced in also.

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Seems easier to just switch the required 5 speed wiring components only :/)

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Exactly my thoughts. I've got a good friend helping me with wiring, who is experienced with wiring and diagrams, personally wiring is the bane of my existence. He was trying to tell me it'd be a lot easier to add the limited items but after going through ChildrenOfBodom's well documented build thread I'm starting to think the opposite.

I would not mess with the body harness at all. Once you see what replacing it entails you will agree. My suggestion would be to replace the engine wiring harness and the ecu with a 99 5 speed and then integrate the existing body harness the best you can

I have connections with an ECM reprogramming company and shouldn't have a problem reflashing manual data onto the existing auto ecm. I think 99 manual ecms are going for a premium on ebay currently ($400-$500). I will look for a manual engine harness as that shouldn't be too much money.

Now I do have a full engine harness from my 97 donor along with the manual ecm. Is there any issues 97 sr5 ecm vs 99 limited body harness?

I swapped a 97 and on the older models the ecu plugs do not fit from the manual to auto even for the same year. Therefore it was easier for me to switch both the engine harness and the ecu. From what I have read the new models 99 and 00 have better compatibility with the plugs. The real reason to swap the ecu is that when all the auto transmission functions are cut the ecu will throw a check engine light. The starting circuit ,reverse and neutral switch can all get rewired off the manual transmission using the auto ecu. I really have no idea if you can reflash the computer to overcome the problem of the check engine light. My opinion is the 97 engine wiring harness will not help you at all. A 99 5 speed engine wiring harness might help a little and a 99 manual ecu will help the most

I will be interested how you make out. My recently bought 00 5speed I'm chopping for parts, I plan to strip out all the 5speed related items. I mainly bought it for a donor transmission 5 spd to 5 spd swap cause my 1st gear syncro is crunchy. So I'll have everything I need to do a auto to 5speed swap in the future.

Also 97 4x4 manual ecu's are selling for 400$ on eBay too so you can just sell the 97 ecu and use the money to buy a 99 ecu

alright i'll get my 97 ecm on ebay pronto.

The truck runs and drives just fine I'm just looking to not have to jump the A/T plug and have a speedometer again.

Thank ya'll for the input!

Really?! Man, that sucks.
@koelt swapped his '97. He says he did it in 4hrs, so I'm sure he just jumpered the neutral switch and had/has a CEL. Maybe he can help out though.

My '01 was super simple. '03/04 Taco ECM is plug-and-play, and I only had to grab 4 wires behind the glove box to make the clutch start SW, cruise cancel SW, and clutch start cancel button all work like factory.
I assumed all swaps were this easy if you got the correct year ECM.

Thanks for the mention... I had a lot of 4WD wiring included with my swap... realistically, the 5 speed stuff was the easy part.

Swapping body harnesses between years (especially with well known electronic and generational changes) sounds like a far more difficult undertaking.

My vote is to add the few items to your existing harness.

That seems to be the way i will be going. You had the same year manual ecm and engine harness correct?