5.71s

[nothingface5384]

hey i know theyres bad rep about 571s...and fromsome other people anything over 4.88s...but like i read and understand automatics are for forgiving on parts compared to a manual...and the key to long lasting gearsets is the install.

i was just wondering how strong a 5.71 gearset will be in an automatic....along with being cryno treated...compared to say a reg 5.29 gearset/ 5spd combo....would they be comparable?

thanks

[mudwiser316]

i know of a few people that are running or have ran 5.71's with no problems at all. it's all about setting the gears up correctly and using good gears. just my $0.02!

what size tire are you going to run? later!

[nothingface5384]

if yukon caries a 5.71 gearset then thats then brand i'm going for..i'm stilling thinking about sending them out to get cryno treated, but i'm considering running 36x12.50s on a 15x8 inch rim...maybe 14.50s on a 10inch if i use fenderflares

[fourwd1]

5.71's are totally misunderstood by the unknowing. And cryo treated ones would be even stronger.

And yes, an auto tranny creates less stress on the drive train. The torque converter creates a cushioning effect.

[mudwiser316]

i don't know much about auto tranny's but i would figure 5.71's would be over kill for a 36 tire. now this is only if the truck is a dd. now for offroad only i can see it. 5.29's would be a gear for 36's and a dd. just my $0.02! later

[Sean]

If you plan on street driving cyro treatment will actually make the gear set wear faster.
It does make sense that the higher the gear ratio the weaker the R&P. The drive pinion is only engageing the ring gear a few teeth at a time, the higher the ratio the smaller those teeth are.

[fourwd1]

mudwiser316 said:

i don't know much about auto tranny's but i would figure 5.71's would be over kill for a 36 tire.

You said it right, you don't know much about about auto tranny's.
Sorry dude.
Proper gearing for an auto is typically one step lower than a maual tranny, so for 36's and an auto 5.71 gears is correct.

And the rumor of 5.71's being weak is old school.

[live4yotas]

There is a guy running 5.71's here with on problem with 38" thornbirds. I ran 5.29's in my tacoma 4cyl. auto with 36" tsl radials and they were the perfect gear 80mph at 2700 rpm's. Yukons are excellent gears. I wouldn't cryo treat them I think you will be fine. Unless this going to be a floorboarded daily offroader. Just my opinion man.

[ckingfire]

I hear fourwd1 saying that the rumor of 5.71's being weak is old school, but there are still popular toyota offroad companies (All Pro Offroad) saying that they are. So who are we supposed to believe??

[rockcrawlintoy]

i have broke 5.29s i always worry about it. any gear can break esp when u are 223:1 and have 40 inch tires. i think a 5.71 will break before a 5.29. but also i think a 5.29 will break before a 4.88 gear i did find a way to not break. I am building a 14 bolt for the rear no more 7.8 ring gear hehe 10.5' ring gear with a 3rd pinion bearing.

Drew

[live4yotas]

Yeah 5.29's will break with a stock motor and 39.5 boggers with a lead foot. Buddy of mine went through three 5.29 gear sets in a week. Solved the problem with 4.88's. Never broke those.

[live4yotas]

It all depends on the driver and what the truck is going to be used for. I dogged on my tacoma all the time and never had a problem with 5.29's. The truck was my daily driver. But was never offroaded hard. Mud riding and crap like that. Street queen that weekend mud rides I couldn't see having a problem with 5.71's. I'm thinking about using them in my 85 yota build. But All Pro Offroad and what they put there trucks through I couldn't see 5.71's working the pinion gear is to small and is the weak link.

[skydso]

I just bought a 1990 3.0lt Surf petrol V6 auto tranny but have no idea as to what gearing it has. On the other hand, I had bought a pair of 4.11 diffs. Will the truck do fine on the road and off it with this ration?
Cheers?

[fourwd1]

Find out what ratio you have now.
Get the axle code from the tag on the firewall, a letter and 3 numbers (G252 for example). Then check one of the online charts to decode and find your current ratio.

Whether or not 4.10's will be of any use depends on your current ratio AND your tire size. Chances are the 4.10's won't be of any use. Probably what you have now.

[skydso]

So what gearing should I use for urban driving, no motorway whatsoever but a lot of rockcrawling on a V6 3.0lt with auto tranny and 30" tires? Not bothered about speed at all as the speed limit here is 50mph and I could use the extra fuel saved when not flooring it as gas is VERY expensive here! It's about $1.50/lt here! All I want are torque, driveability, RELIABILITY and fuel economy!

[fourwd1]

What ratio do you have now ?

[skydso]

Don't know yet as I only just bought it and drove it around a little bit. Besides, it's not in my possession yet. Was thinking of asking you lot first to later check what ratio I have and if it's not what you suggest to me, I'd be able to order the new gearing straight away, without having to wait for answers on here or whatever ...
ps: it's a '91 Surf 2 door.
Thanks
Dave