FireMan

I've asked this a couple of times now, but new threads always seem to get more attention.

Concerning a 3.0 to 3.4 swap:

To the best of my knowledge, (and I forget things very easily)

1.There is no known way to swap the 3.4 if you have an auto tranny. The ECU can't/won't function with the old tranny.

2. If your car has 4wd currently, (like me), if you swapped a newer auto tranny with your new 3.4, you would loose 4wd because the output shaft on the trannt/t-case is on the drivers side.

3. It is possible to get an older tranny and convert the auto to a manual. You do need to find an engine that was a manual though.

I really like my automatic, especially in freeway traffic. I also like my 4wd. I like to run trails where you can go fast. I usally only use 4wd to either run beaches/mud, or get me out of a place when I become stuck in 2wd. Is it possible to move the front diff to the drivers side? Or would I have to fabricat new mounts?

Can you swap the axles and parts from one side of the front diff to the other and visa versa?

I believe someone was attempting the swap with their auto tranny, but I don't think they have gotten anywhere yet. Does anyone know of a successful 3.4 swap with an auto?

Flygtenstein

1. No. You can either use the auto that comes with the 3.4 or others claim to have used the stock auto but have not explained how.

2. No. In order to keep 4wd on your truck, you swap the new tranny but use an adaptor to get gear driven passenger drop t-cases. This makes it time to get a crawler.

3. Sure, you could use a stick.

Sure you could move the diff. Sounds like the most labor intensive solution to an otherwise simple problem.

No, you cannot just flip the diff and the stub axle to get the diff on the other side.

No one has posted here with a 3.4 auto swap yet.

mt_goat

[QUOTE=Flygtenstein]

2. No. In order to keep 4wd on your truck, you swap the new tranny but use an adaptor to get gear driven passenger drop t-cases. This makes it time to get a crawler.
QUOTE]


I didn't know you could get a crawler for an auto. Or is it a crawler for a 5-speed that will adapt to it? Does anyone make the adaptor?

Highland Runner

I want to do this swap one day but I have an auto. The best thing to do would be to convert the transmission to 5-spd. I don't know of any advantage of having an auto, except eating while driving. However, there must be a way to do it.
I don't remember the reason(s) the old tranmission won't work with the 3.4. Is there extra sensors on the newer auto's? If so, could the sensors be added to the old one? Aren't the tranmissions esentially the same 340 series? Couldn't you just use the newer trans bolted to the old transfer case? I'm going to crawl under my wifes car later to check out the auto.

FireMan

Thats what I thought for a long while.

Fahrenheit 451

Apparenty, Marlincrawler.com does make an adapter plate so you can put a gear drive transfercase on the auto. I didn't think he did, but I saw in a reply from Marlin on a different board that he does make an adapter for such an application. The automatic has the major advantage of being a fluid coupling instead of a mechanical one; much less stress on the drivetrain. It has the major drawback of being a fluid coupling in that it has lousy downhill traits resulting in Hold on Nelly! descents.
The only big deal with the automatic conversion on the 3.4 that I remember reading about is making sure that if you have an auto that you get a 3.4 from an automatic set up 3.4 due to potential problems with the machining on the crank for the pilot bearing and to have the correct ECU. You need the ecu from the donor 3.4 to match the tranny set up.
Caveat: this is info gathered by a "web wheeler"

Duh....just did a quick check and I am wrong. The bit on the auto is just about the pilot bearing and not that the automatic can still be used. Sorry. Looks like a manual tranny only swap for now.

Bigblock

So the auto 3.4 has no pilot drilled in the crank?

Skin N Nutz

Some do have the pilot bearing hole, you have to check each engine. I have an 2001 3.4 that was an auto and it has the pilot bearing hole in the crank.. I have heard that some of the older 3.4's didn't have it machined in, and most of the newer ones do.

Also, the older and newer automatics are very different and cannot have sensors added or changed. It would be best to use the newer tranny(Newer is always better) with the marlin adapter to a 21 spline pre 89 transfer case. That way you can double it up. Plus the 21 spline is one of the strongest toyota t-cases made.

rockota

TeamShiftPoint has done a number of 3.4 swaps with the stock 3.0 a340H auto tranny... See this thread for info...

mt_goat

I agree it would be better to use the newer tranny, but there is some misinformation in this statement. First, the gear driven transfer cases were avaliable in the US until 1995 with the 4 cyl models. 2nd, Inch Worm makes an adapter now for the older A340H trannys to adapt them to the gear driven t-cases. 3rd the 23 spline gear driven transfer case is stronger than the 21 spline and is recommended for dual cases. http://www.pirate4x4.com/forum/showt...fer+case+mount