Topic: best gearing!!!

[4runnin_87]

alright ive been talked into the right gearing im going with the 5.29 yukons...thanks for all the help

[blackdiamond]

alright ive been talked into the right gearing im going with the 5.29 yukons...thanks for all the help

If you are worried about strength, have Bobby Long cryo the front ring & pinion.  I don't know the specifics, but I have read that it doesn't help in the rear differential.

 

[Hottrod81]

If you are worried about strength, have Bobby Long cryo the front ring & pinion.  I don't know the specifics, but I have read that it doesn't help in the rear differential.

 

I think the Cryo is recommended for trail rigs only, not DD.  I don't know many of the specifics either.

[bluetoy84]

Cryo treating makes the gears softer which equals less chance of breaking , but also makes the gears wear faster.

I used to think that the lower ratios where weaker just because of all the crap you hear about it, but I have since changed my opinion due to what I have seen on the trail. Yes, you will likely see more broken 5.29's than any other ratio, but 5.29's are by far the most common gear used in trail rigs. This would be like saying a nissan is better than a toyota because you see less broken nissans than toyota's on the trail. Why is this? Because there are less nissans on the trail. If more people ran 4.11s you would probably see more broken 4.11s. Like I said earlier, there are thousands of people running 5.29s in hard core trail rigs.

The key is a quality gear, and a quality set up.

[bluetoy84]

Also for all you 5.71 haters out there, this is my buddy's truck. 5.71s and 38.5x14.50 SX's this truck has seen an unbelievable amount of abuse for almost 2 years with no gear failures. Some people will tell you 5.71s will break in your driveway. I disagree. 

[Hottrod81]

Also for all you 5.71 haters out there, this is my buddy's truck. 5.71s and 38.5x14.50 SX's this truck has seen an unbelievable amount of abuse for almost 2 years with no gear failures. Some people will tell you 5.71s will break in your driveway. I disagree. 

Where was that taken, Hollister?

[blackdiamond]

Also for all you 5.71 haters out there, this is my buddy's truck. 5.71s and 38.5x14.50 SX's this truck has seen an unbelievable amount of abuse for almost 2 years with no gear failures. Some people will tell you 5.71s will break in your driveway. I disagree. 

The front tires look to be spinning at different speeds, is the front diff locked?

[bluetoy84]

Where was that taken, Hollister?

Nope  , definately not Hollister. Try Alabama. Check out the link. Be sure to click on the video promo to see how we drive here in the south. 

http://www.rocketcityrockcrawlers.com/competitionstuff/2006_king_of_the_hill.htm

And yes, The front diff is locked. EZ-locker and 30 spline longs. 

[cheap sunglasses]

Cryo-treating was just discussed in greater detail on pirate. There is nothing wrong with croying DD gears, both front and rear. Cryo'ing them does not make the metal softer, it just rearranges the molecules to reduce stress risers. Heat treated gears (annealing) is what you don't want on a DD in the rear, although it's no problem in the front unless you drive on the freeway in 4wd ( ). The heat treating is what makes the metal sof/less brittle to protect from shock damage.

[4runnin_87 [OP]]

oh ok i see

[bluetoy84]

Cryo-treating was just discussed in greater detail on pirate. There is nothing wrong with croying DD gears, both front and rear. Cryo'ing them does not make the metal softer, it just rearranges the molecules to reduce stress risers. Heat treated gears (annealing) is what you don't want on a DD in the rear, although it's no problem in the front unless you drive on the freeway in 4wd ( ). The heat treating is what makes the metal sof/less brittle to protect from shock damage.

This is good to know. I was under the impression that cryo-ing stock birfs made them wear faster. I'm no metalurgist, just a dumb machinist. I have a lot of experience with heat treating, but not cryogenics. Thanks for the info.

[Hyena]

a good running 22r will push 37's just fine with 4.88's.  my buddies truck is like that.  his truck would cruize the freeway in 5th gear up hills.  i don't see why you would choose a prooven weaker gear ratio.  but to each their own.

[DTB]

a good running 22r will push 37's just fine with 4.88's.   his truck would cruize the freeway in 5th gear up hills. 

hmmmmm....i just can't see that. If that was the case then everyone would be running 4.88s.

[Hyena]

hmmmmm....i just can't see that. If that was the case then everyone would be running 4.88s.

Well, his truck did it.  rebuilt stock 22r with stock carb and it ran great.  37 in MTR's and 4.88's.  i had 5.29's and 35's with my old 22r which wasn't in bad condition but his truck was faster.  it mostly depends on the engine.  105 horsepower and 90 horsepower is a big difference in these little engines.

[Hottrod81]

Well, his truck did it.  rebuilt stock 22r with stock carb and it ran great.  37 in MTR's and 4.88's.  i had 5.29's and 35's with my old 22r which wasn't in bad condition but his truck was faster.  it mostly depends on the engine.  105 horsepower and 90 horsepower is a big difference in these little engines.

I have 4.88's and my truck pulls my 36"Iroks in 5th gear just fine.

[Rocksurfer]

I love these threads, they always comes to the same conclusions: go with 4.88's for their strength and you'll be just a tad underpowered or go with 5.29's and you'll have the power but will sacrifice the strength.

[ZUK]

i am going to start building my truck soon and want to find out what you guys think would be the best gearing for 35-37's on the trail as well and on the street because this will be a dd also

bigorange- using the basic relationship...

4.10/28" = X/37"  ....solving for the gear ratio  "X"

X= 5.42  this means if you were to go from the factory 410 gears and 28" tires to 37" tires that you would need 542 gears to make the speedo read accurate again. Now, of course, the 37" tires are a bit heavier than 28" tires so standard procedure is to gear down just a little bit more to help turn those heavy meats...that means 571 gears, in this case. That's 5% lower than factory over-all gearing with tires taken into consideration. Just make sure the gears are pro installed and they will last just fine. ZUK

ps---the basic equation I used will work with 33 and 35" tires also.
I did the math for 33 and 35" tires below.....

35" tires  =  5.12 gears
33" tires  = 4.83  gears.

[Hottrod81]

I love these threads, they always comes to the same conclusions: go with 4.88's for their strength and you'll be just a tad underpowered or go with 5.29's and you'll have the power but will sacrifice the strength.

I agree

[ZUK]

  proud of you guys....I see that rocksurfer...bluetoy84.....and yotaboy79 understand what gear strength is all about....it's the gear quality and the actual gear install. 

If I were to put 37" tires on(22R or RE) and I knew I was gonna keep them on...it would be 571 Precision gears....
If I thought I might go down to 35" later on then it would be 529 gears.

This would keep the rig geared correctly both on and off the road. This being on a rig that sees double duty....offroad and onroad. The clutch will thank you for it, of course.

I have run deep gears numerous times in the past....In 1986, I was running 33" tires and 571 gears on my daily driver 84 Toy truck/5 speed/22R...that might seem too low geared but back then the speed limit in AZ was 55mph so it was ok on the highway.

Just last year, I was running 33" tires and 571 gears on my 87 Runner...but that was an auto so it was even better on the freeway. 75 mph at 3400 rpm.

My trail rig that I recently sold was a 1992 Toy standard cab/22RE/5 speed with a flatbed and 36" TSL tires with 5.89 gears(dana44's). It also saw the highway for trips to Moab and California with no trailoring. It was revvy at 70 mph but still doable on the freeway.

Happy Thanksgiving! ZUK

[Rocksurfer]

Where's your shop ZUK I just moved from CA to AZ, I'm in Gilbert.

[ZUK]

Where's your shop ZUK I just moved from CA to AZ, I'm in Gilbert.

My shop is my 2.5 car garage located in my backyard alley access. By the grandfather clause, I am the only known alley access garage I know of
I'm very close to Ray/Arizona ave.
A lot is going on now.....taking a trip to SLC, UT in a couple days.....a Carribean cruise in mid DEC.
So I'm holding off on the gear installs for a little. ZUK

[yotabj]

Well, his truck did it.  rebuilt stock 22r with stock carb and it ran great.  37 in MTR's and 4.88's.  i had 5.29's and 35's with my old 22r which wasn't in bad condition but his truck was faster.  it mostly depends on the engine.  105 horsepower and 90 horsepower is a big difference in these little engines.

Well you you explained alot ther Hyena..37" radials are lighter,I can run 85 or 90 on 36 buckshot radials.(I know cause I drove to Tellico AND Back (Like 160 miles 1 way)But when I run my 38 sx's I am lucky to hit 65.I am running yukon 5.29's and have been for almost 2 years with 2 trips to tellico and back on them so far....Before in the I had Genuine Gears in the rear and it with stood 5 trips to tellico roughly got 30,000 miles out of them..I ended breaking the rear because all the weight of my truck was on 1 tire that was flexed into my toolbox .If it wasn't for that i believe i would still be runnin the same gear set.I also believe it is all in the  setup ..Also my truck has a unknown amount of miles with no mods other than exhaust and a comp cam