RDubya

iTrader: (1)

Hey this has probably been asked a few times in the history of this forum, but maybe not with these specs.

I have my 94 4Runner 5VZFE supercharged swap. I have 4.88's. Front diff is wearing out, I have replaced it once already and I am going to do the rebuild on the stock unit and then swap it in with a rear E-locker potentially, as the rear is getting louder and will eventually need work.

I want to regear the machine for highway work, I'm not concerned about rock crawling, some off road and a bit of pulling trailers but I am supercharged and ready to add a meth inj system here shortly. I get very poor mileage, maybe 15mpg hwy. Mixed I feel is under 10.

Currently turning 31x10.50 R15. Would like to eventually go to 33x10.50 for the added height.

Would going 4.10 be a significant drop in torque? Should I go to 4.56? I know the 4.88s make for 32-3500 rpm at 75. Burns a lot of fuel. Seems to have a hard time dropping down into OD at that speed.

What do you guys think are my best options?

JasonYota

iTrader: (1)

What I plan on doing for mine is installing a used 4.10 3rd member in the rear axle and testing it out for a while to see how it does. Before spending quite a bit more for new gears.

RDubya

iTrader: (1)

Not a bad idea. I guess I'm just looking for opinions or experience with the 4.10s and the 5vz. I have lots of low end power. Rpms are too high on the highway. Can't imagine i would lose that much power moving to 4.10. It'd be nice to swap one in if I could find one. Local j/y never has them. They are going every time I go. Limited selection these days all the trucks are getting old and a lot are already crushed.

BigBluePile

iTrader: (3)

Auto or manual?

For 33's you might want to stick to atleast 4.56 or maybe 4.30's....

I run 4.88's on 35's, if I go 37's we'll see how 4.88's go as I may have to go to 5.29's. Really depends on your road to offroad ratio is.....? If you spend the majority of your time onroad, then stick to a higher ratio.

RDubya

iTrader: (1)

it's an auto. stock 94 auto a340h built slightly to handle the extra power provided by the 3.4 swap

So far it runs great, but the low gearing in 1st and the OD makes it shift abruptly into 2nd and the RPM's are high, 3200+ at 75 mph. It tends to drone at that speed due to engine noise and possibly bad rear carrier bearings. Want to rebuild the front to match the rear e-locker I will install this summer.

I don't want to go to 4.10s and regret it when I tow or go to 33x10.5 r15 and not be able to get it to go into overdrive without going 100 mph

Is the 4.10 mainly just manual trucks or smaller tired autos?

odonekanobe

I have a S/C'd 3.4 in my '93. Except I am a manual. Original ratio was 4:30's, swapped to 4:88's when I found an ARB front with 4:88's. I really miss my 4:30's. I am turning about 3,000 RPM's at 70mph. Mileage is about 16, with the 4:30's I could pull 19mpg freeway. This is on 35" mud terrains.

Many 4runners came factory with 4:30's, especially the 3rd gens which you could then get a 4:30 e-locked rear and not have to touch it except for the housing mods. You have a much smaller tire than I am running, and the same motor. Power was never an issue for me.

RDubya

iTrader: (1)

Hey cool, thanks for the info

My only real concern at this point would be going to 4.30 would I be dropping in and out of overdrive all the time with the auto. I suppose if I was towing I would want to keep it out anyway and I could use the OD off switch and power. I am purchasing a methanol kit this week, I had some issues this summer with heat while towing, and this will be my next project to tackle. I think I have located a decent 4.10 rear but it will likely need a rebuild, I think its probably best to do it to make sure its solid before installation. I will just change gearing at that point. so 4.30 would be two steps from 4.88, my estimation is that it goes about 250 rpm each step. But 33's would also drop it a step.

Am I right or at least in the ballpark on the rpm's?

donomite49

i have the stock 410's in my truck with 31" tires and a 3.4 auto.

thinking about 33's with the same gears to lower highway RPM and better mileage.

odonekanobe

What RPM's and mileage are you getting with your setup? Being that the OP has an auto your info might help him more.

RDubya

iTrader: (1)

yeah man, are you using the 3.4 a340f trans or the 340h from the 2nd gens?

I suppose it shouldnt make a huge difference. What kind of mileage are you running? Can you give me an idea how high your rpm's are at 75?