I have a 1989 sr5 pickup manual 4x4. In the summer of 2016 I plan on attempting the swap. I've got the engine, engine wire harness, body harnes and ECU 3.4. I also have things like the factory crossover pipe, flywheel and catalytic converter, with the two o2 sensors, all from the same truck. I also have the vin from the donor truck and a 3 inch body lift. From what I can tell it will definitely be worth buying a pre-fabricated crossover pipe. I'm not sure of is the wire harness. Is their a company that is still in operation that offers something to aid with the wiring? Any advice would be much appreciated and I will continue to post while I'm performing the swap to help anyone out in the future.

 

http://www.toyonlyswaps.com/

Send them your current cross over, they'll modify it to drop down the driver side for a fee, currently $175 from their website. I used them for mine and it worked perfectly for me, and the SMOG ref OK'd it (only an issue if you're in California) since it re-used all the factory flanges.

They can also build a conversion harness you. I did my own conversion harness, but I have heard good things about them.

The other option is ORS, http://www.offroadsolutions.com/prod...vz-fe-3-4l-v6/

 

Thanks for the link. If I were going to do the wire harness myself would you recommend a 3.4 and 3.0 service manual? Or is there some other reference I could use to get exact layouts?

 

You'll need both, and unfortunately Toyota doesn't provide a table for each connector to associate a function with a connector pin number, you'll have to work through the EWD (Electrical Wiring Diagram) to build that table yourself. You'll need to do that for both the 3.0 and the 3.4 engine to body harness connections, then it's a matter of matching up the similar functional wires; most will match up easily, but there will be a few that could be problematic, but search through the prior swaps, it's all been covered before (it may just take you a while to find the answer).

Easiest thing to do is cut the ends off the 3.0 engine harness (with 6"+ of wire) that plug into the body harness and cut the 3.4 body harness connectors off (again with 6"+ of wire) then solder the wires with similar functions together and this becomes your "conversion harness."

https://techinfo.toyota.com/
Pay the $15 for 48 hours of access and download all the PDFs for both your donor truck (the 3.4) and the recipient truck (your 89). You'll want both the FSM (Factory Service Manual [repair manual]) and the EWD.

You may have some issues finding the EWD for your 89, as I believe TIS only goes back to 1990 model years.

 

can i use the air box from the 3.0 or am i better off just getting a cool air intake to just simplify things?

 

Now that ORS is back in business I would recommend their harness over toyonlyswaps.com. I have heard some nightmares about their wiring from a few people who tried them out. (they are semi local to me). Good crossover work though.

Read all the swap threads you can on YT and Marlin..

 

I need to know if the oil pan from the 3.0 will fit on the 3.4. i don't mind to buy the conversion kit but i want to use as much of the resources i already have. I know that i will need to get the parts to change and move the sump but it would be awesome if thats all i needed. I also want to replace the timing belt on the 3.4 before i put it in the truck. What belt should i go with? are there any brands i should stay away from? I may even change all the topped gaskets just to start as fresh as possible.

 

Yes, the 3.0 oil pan will work on the 3.4.

I'd recommend using the 3.0 pan (either buy a new one or reuse your current), use the 3.4 baffle (the 3.0's is sandwiched between the oil pan and the block, and is a potential oil leak source), use a 3.4 oil pick up from a T100 (15104-62070, this will work 100% with the 3.4 baffle and fit the 3.0 tank), use a T100 3.4 dip stick 11452-62060 (guide) and 15301-62060 (dip stick itself). This is the set up I ended up using (with the stock IFS setup) and everything went together and fit like factory.

EDIT:
Here's a picture of my first 3.4 with the 3.4 baffle (freshly cleaned up, thinking I was going to need to cut a hole in it for the pick up) and the new T100 3.4 oil pick up:

 

The 3.0 air box will not work, but feel free to experiment and try for yourself. It's designed to mount to the driver side fender, but the 3.4's intake plenum opens to the passenger side with the expectation of a passenger side mounted air box.

 

Hey man you're asking every question that's already been answered 100x. Everybody replying has highly detailed swap threads for this reason. The best advice anyone can give you is read the wealth of information that's already here. The work has already been done for you and anything past that is what they call spoonfeeding When things get truly complicated or you want to post progress pictures feel free!