Hey hey there! i'm new at this so please don't mind me but... i was wondering.... i have a 1990 Reg.cab Pickup with a 5 speed trani. i'm bout to drop in a fresh 22R. i've got a 4 supsenion and 3 body and i really wanna run 35x12.50 on my 15x12 or 15x10 BUT i don't know what ratio i should get. 5.29 or 5.71? think you guys could help me out a lil? thanks

KOA

 

Welcome to Yotatech.

This gets covered a lot so try searching for varying opinions and then pick one you agree on.

5.29 is as far as I would go IMO.
Check out my website for gears.

 

I'm running 5.71s with 35s. So far I have not had any problems with a 22r. Another rig with a V6 and 39x15s has destoried 2 sets of gears now. If this is a trail rig you could go either way. If it is a daily driver go with the 5.29s. Everyone says the 5.71s will break easier than the 5.29s. I am not going to be runner much power and plan on going to larger tires at some point. I don't see much pavement in my truck. The 5.71s and 35s is to low for highway use.

 

5.29 would be stock ratio, but doesn't account for the heavier wheel/tire and the increased rolling/air resistance. I would go 5.71 - these engines love to be revved and hate to be lugged. Your clutch will thank you too.

For everyone who says 5.71 will break and 5.29 is OK - how ya figure? You say that 5.71 is weak because the pinion is too small and has too few teeth. Well, guess what - both 5.29 and 5.71 have 7 teeth on the pinion! Since they have the same number of teeth, there is no significant difference in the strength of the pinion.

What IS true us that the lower the ratio, the more critical the setup. You need someone who REALLY knows what they are doing to setup either ratio.

Check out www.gearinstalls.com for more info

 

TC that's good reading at www.gearinstalls.com. It's the first I've seen that. All the other reading I have done (that was years ago) talked about the smaller contact area and it being "guaranteed to break" (Petersen's 4 Wheel & Off-Road). It seemed that all the write-ups felt the same way.

 

5.29s

 

5:29's

 

Zuk is the Master...

Personally I would go 15x10s and 5.29's but a lot of people have not broken 5.71's. I used to break 4.10's with 35's due to the weight of my right foot in a past truck...

 

X2. This is my experience as well.

 

i broke my 5:29's....so now i got 4:37;s....ive got 36's and i am hoping to go to 4:88 some time when i have the money! but to be fair they were Genuine Gears.....if you get some yukon's that are cryod....you should be fine with 5:29's

 

Who installed them? What was the backlash and the carrier bearing preload? Crush sleeve or solid spacer?

Could have been that they were Genuine Gears (which hopefully you realized have a lifetime warranty), but could have very likely been the setup and no matter WHAT brand/heat treat condition they would have been toast.

As for cryo ... lemme just say I'm a metallurgist, and AT BEST it's a crutch to fix a bad heat treat operation.

 

with out a proper install, all gears/ratios are junk!

 

I'm running cryo'd 5.29's and 35" Trxus MT's in a 96 with a 4 cylinder. I would not go any lower than that. My revs are at 3000 at 75mph indicated.

 

Those revs may be OK with the 2.7, but will be out of the powerband on the older motors. 5th would be worthless until 80MPH indicated (in my truck anyways)

 

when you say "out of the power band" do you mean before or after?
my 2.7's power band is way lower in rpm's than my 22re's.

anyway, in my truck in 5th gear at around 2700 rpm at about 60mph.
and it pulls 5th just fine until i hit a hill lol, then its 4th gear show.
but im running boggers and they are heavy and have allot of friction drag/wind resistance. i put some 37" radial irocks on and it seemed to have more power.
my point is, that it depends on not only the size but the type of tire also.
if hes just gonna run some regular mud terrains then 5:29's would be more than adequate.

 

I mean the powerband starts at about 3000 RPM on the 22RE and 3VZE. If your RPM's are much below that, you're going to have a hard time holding the gear going up even slight inclines or into the wind.

Obviously, power issues are greatly accentuated here at altitude and especially with my heavy ass 'runner (approx 5200 lbs!), but it just makes the truth more apparent - you need to keep the RPM's over 3000 for happy cruising on anything but flat terrain.

 

agreed! though i can take on "slight" inclines in 5th

5200lbs wow! is that the stock weight?

my truck only weighs around 4k, with my 300lb ass, and some heavy tires and winch and blah blah blah.

 

Nope - not stock ... .188" wall sliders, .120 wall bumpers, dual cases, 2"x0.25" wall lower links, 1.75"x.120 wall uppers, crossmembers, skids ... it weighed 4940 lb before redoing the rear suspension in daily driver mode (full tank of gas, just simple tools, jumper cables, spare, etc) with just me in it ... add Molly, the dog, spare fluids/parts and all the extra steel for the suspension, and I figure 5200 is a VERY safe estimate for 'wheeling.

 

I totally disagree. Now maybe its do to the RV cam that I'm running but I do very well with 2700rpms in 5th. Pulls great, stock cam had to be revved so down shifting was a must. Still don't know why people run the 268 cam over 260cam. All I can reason is some of the mega gurus recommend them and some folks can't think for themself, just nod and regurgitiate what they were told.

ZUK has done 5.71's with success.

 

Being that the cam pretty well defines the powerband, that would make sense ...