Topic: 3.4L manual and 35's

[TheTank]

I'm getting tired of getting about 10 mpg with my 3.0 and auto, and I'm about to so my SAS with the '85 axle I just got, and I wanted to swap in a 3.4L with the manual tranny and dual cases.  But my main question is, with 5.29's, the 3.4L, and the manual tranny (possibly with the optional lower gear set-5.15 1st gear), do you think I will still have plenty of power and get reasonable gas mileage (~20-24 mpg) on the highway?  I just can't stand the sluggishness of my 3.0 even after regearing to 4.88's.  It just seems to suck gas like crazy, but I've been hearing that with the DOHC of the 3.4, the gas mileage is greatly increased over the SOHC of the 3.0.  Does anyone have this setup?  I'm getting ready to pretty much rebuild my '91 4Runner with the SAS and new engine and tranny, so I want to get it right the first time and be pleased with the results so I can continue to enjoy this rig.  Thanks for any info you have.

[Skinny_Pedal]

heres where u can get the conversion for that setup     www.offroadsolutions.com

[TheTank [OP]]

Yeah I've got an idea of where to get all the parts and everything I need for this whole rebuild of my truck, I just wanted to hear from some of you with experience with this engine/tranny/gear/tire combo to see if it is going to be worth my time and money to invest in such a project.  I really want to run 35's (maybe 37's later) and just wanted to make sure that this combination would produce good power (much more power than my 3.0) and get way better gas mileage.  I know the 35's or 37's are big tires, but I thought with the lower 1st gear and 5.29's it might compensate for the tire size and get about the same mpg as it would stock.  I just don't want to invest and still get 10 mpg with very little increase in power.  But yeah I was going to go with some offroad solution's stuff for the swap.  Thanks

[Skinny_Pedal]

well in our 97 runner we had with the 3.4 it wasnt a great gas saver. i know it was tons better than our 95 with the 3.0. wish i could help with your other q's

[Thumper]

As for the better gas mileage i dowt it will do much better maby 12 too 14 town lil more on highway but as for power you will have tons more power the 3.4's have about twice the power the 3.0's have stock and you can easyly as a trd super charger too the 3.4 for even more power.
I dont remember what the 3.0's put out stock think its about 145 too 160 somewhere in there but the 3.4's have 190 horses stock and i think 215 ft pds tourqe and with the super charger it puts it up too 265 horses and if you add the 7th injector option that sprays fuel directly into the supercharger it adds another 35 too 40 horses so if you want lots of power i would deff go with the 3.4.
i had a friend with a 95 taco with 3.4 and 5 speed and with 35's it still had lots of power and still got decent gas mileage with stock gears.
so you really cant go wrong with the 3.4 manual swap.
Good Luck
adam

[kyle_22r]

i think with dual cases, you're going to be overgeared with 5.29s.  my buddy runs 4.88s and 5.29s in his taco, and that's probably quite a bit heavier than a hilux/4runner, and it does great

[TheTank [OP]]

So if I do go with the manual and the lower 1st gear set (5.15) then it would be a good idea to stay with my 4.88's even when I get 35's?  That would help out pricewise a whole lot.  Can you tell a real difference having that lower 1st gear as opposed to the stock 3.83?  I can't decide if I really want to go with the 5.15 or 4.31 with the 35's and 4.88's.  Sorry for all the questions but I want to save as much money as possible in the end especially with the gas mileage and power.  One last question, hopefully Marlin you can give me an idea on this.  If I was to purchase the rebuild kit and lower gear set myself, is it that complicated to clean the tranny up and rebuild it in my garage?  What special tools are involved besides the bearing pullers etc.?  I have a pretty good knowledge of the mechanics of my truck and have done all the work on it myself (don't trust the dealer).  I'm going to find a manual from a 3.4L and do all of this work on it, but I dont' want to drop the money and then find out someone else has to do the work.  Thanks guys

[kyle_22r]

with a 5.15 first you'd better feel a difference!  with anything more than 4.88s it'd probably only be useful as a granny gear   i'd definitely stick with them, you'll have no complaints

[Mike D]

I would go with the 4.3 chevy vortec it would average about 12-15mpg but if you don't like the gas milage why did you have a lifted truck.

[TheTank [OP]]

Well I knew the gas mileage was going to go down, but this 3.0 has 194,000 miles and is just getting worn out.  I know I'm not going to get anywhere near a reasonable mpg with a lift and bigger tires, but I though anything would be better than getting like 9 mpg that I've been getting lately with my 3.0 and auto on 33's.  I'd rather stick with all Toyota stuff anyways and maybe add the supercharger later.  But it sounds like 3.4 with manual and 4.31 gear set and 4.88 R&P on 35's would be an alright setup.  But anything right now is better than getting the gas mileage i've been getting lately.  Thanks for the help

[Mike D]

 

[jvministries]

I was running a buick 4.1 engine 200+ hp with 4:88's and 33's behind a g52 transmission for a while and it sucked as far as drivability way too much gear and terrible gas mileage but I never liked the 4 cyl with the 4:88's with 33's it was too much gear. and I got about the same mileage.  I now have 4:56 gears and a r150f v6 tranny and 35's and dual cases it should be a lot more streetable with the torque of the v6 since it is set up for low end to mid range torque rather than top end hp.

with the 4:88's and 33's I was just winding everywhere I went and 55 with in 5th the engine was running in the 35-3600 rpm range to go 65 it was really winding. I went to 35's and that helped a little but I still didn't like it.

it felt like a drag car with low gears with the old set up.

so the gearing will make a big difference and it may be worth it for the mileage differences to have the extra power

have you looked into the 5 mg and 7 mg engine swaps they offer about the same gas mileage with lots more power
but more power usually means more breakage too.

I like the super charger idea too and the extra injector too get ya 300 hp. just watch out for the transmission at that level.