I have a few questions that have yet to be answered from searching(lots of it).

1.Can I use my 3.0L oil pan or do I need an oil pan from a T100 4x4 and if from a T100 which engine, 3.0L or 3.4L?
2. can I use the 3.4L wiring harness as a direct replacement of the 3.0L wiring harness? if not what would i have to modify on it?
3.How do I get the gauges to work? do they hook up the same on the 3.4L as on the 3.0L?
4.Do i need a bell housing from a R150F 3.4L donor truck or can I use my stock one?
5.What do I do for and exhaust?

most of these questions have controversy so that is why I am asking them.any other info is greatly appreciated since i will be doing this swap hopefully with in the next 2weeks.
Thanks for the help!!!

well, there used to be a link to a site that had extensive information about this, but it seems to be down <img src="/forums/images/graemlins/frown.gif" alt="" />. i am pretty sure you use the 3.0 oil pan. you will have to redo the exhaust system, because the 3.4 comes out on the passenger side. i believe you have to rewire the harness, which is often the most time consuming part (or purchase one).... thats about all i know but there will be many more responses soon..

danny

I haven't done the swap but have researched the crap out of it. I have found that:
1. Your 3.0 oil pan will work fine, it is the same block so it bolts on, you need your pickup too, and there is some sort of issue with the oil dipstick and tube.
2. The wiring harness will require some work, you will need some good diagrams and a familiarity with automotive wiring. You could drop almost a grand on one if your are really that scared of wiring.
3. I have no idea about the guages but I am sure they will be the least of your worries, tach will be the same for 6cyl, other senders will likely work too. You can look up the specs in Haynes or factory manual to see if the resistances are the same for temp and pressure.
4. I know for sure your bellhousing will work, you need a mixture of clutch parts though, the slave cylinder is on the opposite side of the bellhousing.
5. Buy some headers from Downey (they are under $300) and some high flow cats and mufflers and have an exhaust shop put it all together for you. Should cost about $200 at the shop and whatever the cats and mufflers cost you.

but since i still have the crapy IFS will my 3.0L oil pan work or do i need the T100? And ORS says i need the injector harness from my engine is this true or are they just trying to get more money off of you such as with the oil pan?
Thanks

Well since it is the exact same block bolting up to the exact same engine mounts I can't see why the 3.0 oilpan wouldn't work the same as it does now. You will need a hood scoop or a body lift to clear the intake though, the 3.4 is taller than the 3.0. ORS are crackheads, they want about 400% too much for their harness, I know they have done a couple of swaps, but they do everything the most expensive way. I don't know what they are talking about when they say injector harness, the injector connectors are part of the entire engine harness, which you will need from a 3.4 donor, along with the ECU.

careful before you go bashing that IFS now... what do you plan on using your truck for? the solid axle swap isn't the solution to all of your problems, and in some cases, the IFS is much better for what you want to be doing... probably even more so with the 3.4, if you wanted a boost of speed for driving on the road. the 3.0 oil will work with IFS, and no ORS isn't lying you do need a harness like they sell.. you can either wire it yourself, or if you don't feel as confident, buy it from them. its not so much they are trying to rip you off, its that they are selling highly specialized parts, and are the only ones I know about on the market doing this.

danny

Ok. I did this swap several months ago and heres my take on it-

You can use your 3.0 oil pan if you run the factory IFS (bolts right up) but you'll need to modify the pickup tube to fit the 3.4 motor. I had to cut off one of the mounts for the tube and trim & dimple the 3.4 splash guard slightly to properly clear the tube. I originally was planning to use the 3.0 2wd T100 pan & pickup but my application went from 85 4cyl solid axle to 88 6 cyl IFS. You will also need to replace the dipstick tube with a 2wd T100 tube and pickup in order to fit your 3.0 pan. There's a little bit of work involved in that depending on the casting year of the 3.4. You will need to drill a hole in the block if it's 99 or newer. If you plan to do an SAS you'll need the 3.0 2wd T100 pan & pickup. I would consult Mike at ORS about the particulars.

Regarding the harness, you'll need to use the 3.4 harness and harvest the plugs from the 3.0 (N2 & N3) that attach to the body wiring. You can purchase one from Offroad Solutions or make your own if you're savvy with electronics. Either way, you need the correct EWD (electrical wiring diagram) for the motor and it would help to have the EWD for your 91 truck as well. Contrary to what others may say, you only need the 3.4 engine wiring harness and ECU, and the 2 other plugs that attach the ECU to the vehicle wiring. (no need for the entire under dash wiring harness) There is quite a bit of work to make this as you need to basically cut & splice every wire going to the ECU to do this properly. You will want to solder and heat shrink every connection if you want it to last.

Regarding the gauges- the temp gauge sender is the same resistance range as the 3.0 so its a direct hook up. the 3.0 oil pressure sender will screw in to the 3.4 block but needs to be extended slightly to clear the alternator. The tach will not work without an adaptor. I can supply you with the oil pressure sending unit extender- $10.00 and the tach adaptor- $45.00. I had to build a tach adaptor as no such beast exists to my knowledge.

The bellhousing will bolt right up to the new motor as well as the 3.0 motormounts- However, the right side motormount may only hit 2 or 3 bolts on the block depending on the casting and whether or not you use the 3.4 A/C bracket. I used the 3.4 A/C bracket and compressor and swapped the top of the compressor from the the 3.0L so the hoses bolt right up. Use the 3.4 flywheel, clutch, pressure plate & pilot bearing, Use the 3.0 release bearing. You will also need to cut the P/S banjo bolt down from the 3.4 to fit your 3.0 high pressure P/S line.

Other issues- use the 3.4 alternator and splice the 3 wires into the original 3.0 harness since the plugs are probably different. Re-route the fuel lines and evap lines. Cut a hole in the hood and use a scoop or go with a 2" body lift. I did a scoop because I don't like body lifts. My scoop is at the following link:

http://www.idmspeed.com/sr6pic01.html

Exhaust is the biggest expense / amount of work- I used Downey Offroad headers for the 3.4 manual transmission and cut them to clear my frame. Then I fabbed it to run past the xfer case and merge just behind it. It's a ***** to get the sensors, cat, muffler all in a short span before the tailpipe. Cost me around $700 for the headers, cat, muffler and labor. I can supply you with the sensor mounts- $10.00 pair. Mike at ORS may have a crossover pipe that will adapt the 3.4 manifolds to the 3.0 routing (left side). This would save you alot of time & money.

The end result is bitchin though! I can scream through the 1/4 mile in just under 15 seconds! (I've got the supercharger)

Excellent info Will! You've got a 22RTE and a supercharged 5FZE? Man, I am jealous. <img src="/forums/images/graemlins/smile.gif" alt="" /> <- Green with envy

You realize that you WILL (no pun intended) be asked for more info on this subject in the future.

Thanks Will! about the wiring though im good with wiring but i will be getting the engine to ECU wiring harnnes, what plugs will i have to change? do the wiring EWD's tell you what color, positive or negative the wire is? and even thought the slave cylinder is on the opposite side on the 3.0L bellhousing it will still work with the 3.4L clutch parts right?
Thanks a ton!

also is there a way to wire it up so the diagnostics and check eng. light still work?
Thanks