Author Topic: gearing an automatic (Read 4319 times)

toy85ota · « **on:** Jun 08, 2006, 09:50:20 PM »

I have an 85 automatic w/od 4x4 with 33's and stock gears, its gutless as hell, with average 12 mpg. What would be the best gears to go with in an automatic, I'm pretty sure the automatic have lower gears then manuals, but they ain't low enough to be pushing 33's. What do you think? Thanks

toynorcal · « **Reply #1 on:** Jun 09, 2006, 08:45:54 AM »

4.88's can run 33's with ease and 35's like stock

5.29's can run 35's with ease and 37's like stock

79coyotefrg · « **Reply #2 on:** Jun 09, 2006, 12:44:17 PM »

they say 4.88's for 33's but that is assuming stock with 4.10's you have 4.30's so i would say 5.29's to give you the best gearing, your mileage will go up around 15-17

ZUK · « **Reply #3 on:** Jun 10, 2006, 08:37:58 AM »

Quote from: toy85ota on Jun 08, 2006, 09:50:20 PM

I have an 85 automatic w/od 4x4 with 33's and stock gears, its gutless as hell, with average 12 mpg. What would be the best gears to go with in an automatic, I'm pretty sure the automatic have lower gears then manuals, but they ain't low enough to be pushing 33's. What do you think? Thanks

I too was worried about the gutless factor with my 22RE pushing an auto with 33x10.50 tires.......I was also aware of the fantastic OD that the autos have......so I installed quality 571 gears and was glad I did.

CTENG in KS · « **Reply #4 on:** Jun 10, 2006, 09:10:11 AM »

If you are worried about the 5.71's being a bit weak due to pinion size, you can have em cryo'd by Bobby Long for like $40.

cheap sunglasses · « **Reply #5 on:** Jun 10, 2006, 10:18:42 AM »

Ive seen the gearing debate countless times, and it does seem 4.88 for 33s and 5.29 for 35-37s is the general consensus. I do have a hypothetical though, what if I were to run 33s as street tires 95% of the time, and run something like 36s or 37s as offroad tires which would include the drive to and from the trails. I imagine I would go with 529s simply because I do not do all that much high speed highway driving and around town it wouldnt matter much. Watcha think?

79coyotefrg · « **Reply #6 on:** Jun 10, 2006, 10:56:05 AM »

Quote from: 79Coyotefrg on Jun 09, 2006, 12:44:17 PM

so i would say 5.29's to give you the best gearing, your mileage will go up around 15-17

ZUK · « **Reply #7 on:** Jun 10, 2006, 03:45:30 PM »

Quote from: CTENG in KS on Jun 10, 2006, 09:10:11 AM

If you are worried about the 5.71's being a bit weak due to pinion size, you can have em cryo'd by Bobby Long for like $40.

I had Precision 571 "4 cyl" gears cryo'd and Flexor(local hardcore here in Chandler area) has been beating them pretty good now for about a year. I commend Flex for having the balls to travel the lesser road and run 571 gears in a "4 cyl 3rd" to boot! The tooth fairy has not been there to visit him

....he has not broke his rear chrome-moly axles neither. 37" MTR's.

Here's the link of his 571 install...
http://www.gearinstalls.com/flexor1a.htm

UPDATE:::: I just talked to Flexor

and got the latest scoop.... He's upgraded and been running 40" IROK's for some time now. He's not very stock in the horsepower department neither.....has a 4.3 Vortec in front of a TH350..................................I asked him about gear carnage on the trails that he's witnessed personally...Flex said he's seen a couple 410's....a couple 488's....and one 529 gearset go bye-bye.

here's his Blue buggy below with the 571 gears on a trail called TWISTED.

79coyotefrg · « **Reply #8 on:** Jun 10, 2006, 05:20:54 PM »

um is there a big rock we cant see

Bazzi · « **Reply #9 on:** Jun 10, 2006, 05:33:09 PM »

zuk.
I have been running 5.71 for a 4-5 years now. and both the front and the rear diff have failed me recently at the same year. The front was just my stupidity the pinion bearing failed and I ditn´t notice it till it was to late. I re tightened it at the trail and when I removed it I had a small chip broken off the pinion and decided to change the diff cause the wear.... The rear was probably going for the same direction but my truck got in the way of another car which hit the tier. resulting the housing to bend braking both my axle bearing and chipping the diff..... I am now having that diff reassembled

Does this make sense to you and do you have any advice for me regarding the installation off the diff..

with regards Bæring (from Iceland)

robinhood4x4 · « **Reply #10 on:** Jun 10, 2006, 10:05:03 PM »

With my 3.0L auto tranny the stock gears were 4.88s with 31" tires. With 33s going to 5.29s put me back to stock, numerically. Generally, my advice is always go to 5.29s with 33s with an auto. General concensus for manual trannies is as everyone else said.

Autos shouldn't use the same gears as manuals, in my opinion.

ZUK · « **Reply #11 on:** Jun 10, 2006, 11:27:00 PM »

Quote from: Bazzi on Jun 10, 2006, 05:33:09 PM

zuk.
I have been running 5.71 for a 4-5 years now. and both the front and the rear diff have failed me recently at the same year. The front was just my stupidity the pinion bearing failed and I ditn´t notice it till it was to late. I re tightened it at the trail and when I removed it I had a small chip broken off the pinion and decided to change the diff cause the wear.... The rear was probably going for the same direction but my truck got in the way of another car which hit the tier. resulting the housing to bend braking both my axle bearing and chipping the diff..... I am now having that diff reassembled

Does this make sense to you and do you have any advice for me regarding the installation off the diff..

with regards Bæring (from Iceland)

Too bad you're all the way over in Iceland.

My advice is to use a quality 571 and Precision (WCD sells them) might be the best for Toyota applications. Use a solid collar on the pinion and tighten the hell out of the pinion nut and shoot for a final pinion pre-load of 10 inch/pounds on new bearings. On the carrier bearings, set the backlash for the usual 8 thou or so and tighten the spanner rings (for the carrier bearings) between 100 and 150 ft/pounds. Use a synthetic oil in the rear end application.

That's my 4 sentence advice

um is there a big rock we cant see? Yes.....it's a V notch....can't get thru it with sheet metal. Flexor was favoring the right which put the right tire hard into the wall.

toy85ota · « **Reply #12 on:** Jun 11, 2006, 02:43:07 PM »

ya my yotas is a daily driver, with normal weekend wheeling. So I'm guessing 5.29's? I dont drive on the freeway very often, so I usually dont go over 60.

robinhood4x4 · « **Reply #13 on:** Jun 11, 2006, 04:20:45 PM »

My advice is do the math. Figure out what ratio you have now and what size the stock tires were. Then do the math to figure out what will get you back to stock. It's always good to run the numbers before you lay down the money.

Also, you say you're getting 12mpg, is that corrected for your 33s?

flexor · « **Reply #14 on:** Jun 11, 2006, 10:15:41 PM »

Actually lets give them a more updated picture and actual of whatthose 5.71 are put through.

I now powering this buggy with a 4.3 vortec 350 auto dual cases with a 4.7 in the rear. And its beatin always

And I highly recomend Zuk on gear installs. TOP NOTCH QUALITY AND SERVICE

Rocksurfer · « **Reply #15 on:** Jun 11, 2006, 10:42:33 PM »

Guess I'll give my

on this since I've been down this road, once personally and once with my brother and we used different gearing. I put 4.88's in mine and my brother had 5.29's in his, both were autos and I ran 33's and he ran both 35' and 33's. Mine was perfect with the 33's and 4.88's got decent mileage at about 17mpg. My brother got 5.29's and 35's originally got some crappy mileage at about 15mpg, he then got some 33" Swampers and his mileage increased to about the same as my truck even with the heavy Swampers. I'd go with either the 4.88's or 5.29's but with the 5.29's you'll be reving more at speed.

ZUK · « **Reply #16 on:** Aug 11, 2006, 06:23:25 AM »

Quote from: toy85ota on Jun 08, 2006, 09:50:20 PM

I have an 85 automatic w/od 4x4 with 33's and stock gears, its gutless as hell, with average 12 mpg. What would be the best gears to go with in an automatic, I'm pretty sure the automatic have lower gears then manuals, but they ain't low enough to be pushing 33's. What do you think? Thanks

toy85ota-
...was reviewing this old thread and wondering if you bought any gears yet? I know how gutless the 4 cyl auto can be with big tires and the shell on. Mine came back to life when I changed the gears.
I'll update my 571 link on my webpage in the near future....it will basically show that the "thru torque" is basically the same for all the Yota gear ratios....571 gears might actually have a slight edge and be a few per cent stronger than 410 gears.
Got another thread going on a different board. check it out

http://www.pirate4x4.com/forum/forumdisplay.php?f=12

ZUK

854RUN · « **Reply #17 on:** Aug 11, 2006, 10:45:19 AM »

Zuk your the man

. how is the weather, is it still to hot to do any installs?

ZUK · « **Reply #18 on:** Aug 11, 2006, 08:30:19 PM »

Quote from: 854RUN on Aug 11, 2006, 10:45:19 AM

Zuk your the man . how is the weather, is it still to hot to do any installs?

haha 8) too hot still . I would love to move down to Tucson....100 miles south of here but it is a little cooler

....and the trails are so much closer!

jimbo74 · « **Reply #19 on:** Aug 11, 2006, 09:12:10 PM »

thebeast8888 has 5.29s with 36s on his truck with a stick and its still gutless......

i say go with the 5.29s for the 33s

toy85ota [OP]

Related Topics