3.73's to 4.88's = trouble!!!!

I'm driving a 2006 toyota tacoma with a 6 inch procomp suspention lift with 35's. I have a flowmaster catback exhaust system, jba headers and a CAI... All these mods work well and have had no trouble with them. The issue im having is my gearing... im running 4.88's from a stock 3.73. I have been through 2 sets of gears in the last year. The first set was due to abuse offroading but the second is a little fishy... I think the diff is too small to be running this setup. My tranny is manuall wich definately doesnt help. Im considering swaping the rear axle. Would a Tundra axle fit? Has anyone experienced anything like this? Its easy to find an axle to fit but i want to keep the abs and all the other electronic devices. Any suggestions anyone?

 

There is an underlying problem there. There are people here funnung 4.88's with no problems at all. Did you do the install?

 

the problem is not the gears, it is your mechanic not setting them up correctly.

 

^x2. Thats what i was thinking something is not set right. If the ratio was too big for the diff they wouldnt sell it.

 

off-topic, but how can someone quality the acceleration difference when going from 3.73 to 4.88 on pavement! i understand the reasoning from an off-road perspective but i'm curious about how much faster it makes the truck ON road. man, when cruising on the highway the revs have to be so much higher, no?

 

I cant tell you how much "faster", but i can tell you the truck will actually be slower. It will accelerate much better, but your revs on the highway will be a little higher.

 

How do they fail?

 

Probably need to go to a shop that rebuilds transmissions and rears and have them set it up for you.

The 4.88 gear is gonna give you ummph at take off but kill your top end. There are several sites http://www.rocky-road.com/calculator.html that you can enter tire size and ratios and get your speed differences. I would think your truck is gonna say 95 or so and you will be going 60 mph range with those tires and that ratio.

 

Actually the truck speedo will be just about right on. Because with the bigger tires, your speedo is going to show low, then you correct it with gearing. And the difference would not be that great. I am running 35's on stock gearing right now and i am only doing 5mph over what the speedo says.

 

Pretty cool link

 

I am on the other end of the spectrum. I have a S/C X-Runner. I went from 3:15 to 4:10 and I have a T56 magnum 6 speed trans. Acceleration is great. The T56 Magnum has 0.74 for 5th and 0.50 for 6th (this is the Ford ratios). At 85 mph I am looking at 2100~2200 rpm, in 6th.

 

i think it is your mechanic setting the gears incorrectly, talk with chase at eastcoastgearsupply.com or call them, they know their shit and have an awesome warranty, theyll even assemble it and ship to you

 

I have a 2010 automatic with 35's.A local 4x4 shop said the only gears I could use are 4.88. I was thinking 4.56 would bring it closer to stock? can I use 4.56 gears?

 

You sure can use 4.56's.

 

Did you go to 4wheel parts!?!? If so that is your problem!

Sorry about it dude hope it gets worked out

 

He's in Ontario Canda, probably 500 miles from the nearest 4WP.

 

Folks jumping at conclusions in a big way here. Definitely need more info from the OP about how the failure occurred.

 

nothing new with gears breaking in our tacos..i know a few who have broken stock gears under mild off roading conditions..

and i just recently broke a 4.56 set driving around the neighborhood , but i do agree...our rear ends are too small