Rear End Gear Question?

[t.walton]

Ok Im new here.I have a 2005 Chevy Silverado Cre Cab Z71. I just put a 3" lift in it courtisy of torsion bar keys and 2" blocks in the back. I have 22" Wheels with 35" Nitto Terra Grappler All Terrains on it. What I want to know is it came with 3.73 gears in it. What do I need to do to get my gear ration back to stock ration with the big tires. Any info you guys can help me with I would greatly appreciate it alot. Thanks

[96chevy7.4L]

to get your RPM's back you would need atleast a 4.10 rear gear maybe more.

[Bowler807]

Check out this site. It has a matrix of tire size vs gear ratio. http://www.4lo.com/calc/geartable.htm

[Matt_]

I dont like those gear charts because Jeeps, Fords, Dodges, Toyotas, Fullsize, SUV, etc etc all have different power/weight ratios and transmission ratios.... you can not generalize every vehicle in a single chart and they tend to be misleading.

 

To the OP. With 35" tires you're going to want 4.56. If you have 3.73s now it will be a complete waste of money to get 4.10s.

 

With that said..... if you got 3" of increase ride height from those "torsion" bar keys, your upper control arm is probably riding on the droop stops. Check and make sure they're not. And you might want to consider a suspension lift, or a body lit + decrank. You will spend the money that you would've spent on a suspension lift on front end parts in the near future with 3" of crank + 35s.

[cliobogger]

wow, 3 inches out of your bars...ur gunna kill parts man. and id go with at LEAST 4.56. u said its 4wd so you will need to replace both front diff and back diff gears. both have to be the same ratio. i use the following site to get all my gears and what not.

 

http://www.accuautoparts.com/

[t.walton]

wow, 3 inches out of your bars...ur gunna kill parts man. and id go with at LEAST 4.56. u said its 4wd so you will need to replace both front diff and back diff gears. both have to be the same ratio. i use the following site to get all my gears and what not.

 

http://www.accuautoparts.com/

 

 

Im waiting on my 2" shock extensions right now so I can turn the torsion keys back down. I know what your saying about being hard on parts. Then it wil ride even better up front its a little rough right now at times. Im learning and been trollong on this websit for awhile learning. Thanks for all your guys input and advice its greatly appreciated alot.

[Matt_]

Do not install stock extensions! Your suspension can compress just as much as stock, if you put those extensions on you will blow out your shocks if you hit a bump/rut/etc.

 

The angles of your control arms and the deceased mechanical advantage over the torsion bars along with the increased load requirements to compress the suspension as a result from "cranking" cause the rough ride, not just the shocks.

 

Look into a suspension lift or a 2 to 3" body lift.....

[t.walton]

Do not install stock extensions! Your suspension can compress just as much as stock, if you put those extensions on you will blow out your shocks if you hit a bump/rut/etc.

 

The angles of your control arms and the deceased mechanical advantage over the torsion bars along with the increased load requirements to compress the suspension as a result from "cranking" cause the rough ride, not just the shocks.

 

Look into a suspension lift or a 2 to 3" body lift.....

 

I have read to that longer shocks will help out also. instead on the shock extensions. Any input or feedback? Or suggestions on what shocks?

[Matt_]

A quality aftermarket shock may help some but won't improve ride quality much.

 

You also don't need "longer" shocks. Any quality aftermarket shock has a constant damping coefficient throughout its range and will also not be the limiting factor in suspension travel.

 

Jack the front of your truck up and look at your upper control arms. The metal tab that they're resting on is what's limiting travel.

[t.walton]

A quality aftermarket shock may help some but won't improve ride quality much.

 

You also don't need "longer" shocks. Any quality aftermarket shock has a constant damping coefficient throughout its range and will also not be the limiting factor in suspension travel.

 

Jack the front of your truck up and look at your upper control arms. The metal tab that they're resting on is what's limiting travel.

 

 

Just did that I have about a half inch yet.... I need new front shocks Ive been on a budget lately since being laid off. I just put new rear shocks on a month ago b4 the lift and tires in the last week.

[Matt_]

You have a half inch of clearance there? There's a half inch at normal ride height....you're looking at the upper control arm droop stops, not the lower control are bump/compression stops right?

 

If you need new shocks anyway, get some bilstein oem replacements, they'll have plenty of travel.

[Matt_]

When you get a chance, snap some pics of your front suspension so we can see what kind of angles & such you're running.

[t.walton]

When you get a chance, snap some pics of your front suspension so we can see what kind of angles & such you're running.

 

Yes Im looking at the top. I even have my buddy over here thats a good with this stuff. He has a kick ass 2003 2wd that he has converted into a pre runner. I have Kayaba Mono max that I just put on the back. I have always been a fan of KYB.

[Matt_]

KYB is fine too....

 

But to be clear, you have a half inch of clearance there with your front jacked up by the crossmember and the suspension sagging?

 

If you do, disconnect the shock to see if your susp drops more, if it doesn't you may have another issue like a CV binding.

[t.walton]

KYB is fine too....

 

But to be clear, you have a half inch of clearance there with your front jacked up by the crossmember and the suspension sagging?

 

If you do, disconnect the shock to see if your susp drops more, if it doesn't you may have another issue like a CV binding.

 

 

Yes and it dropped also. I just ordered the Billstein for the torsion key lift. I will have them in the AM.