Project Cheetos...to re-gear or not to re-gear my 3FE 80? (1 Viewer)

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Gilbert, AZ.
Goal - noticeably improved freeway merging, freeway travel (maintained speed) and not as much downshifting during hill climbs on long treks when getting out of town.

I'm keeping my ride, not interested in a manual transmission swap and the 33's are just fine by me.

Factoring in the labor for someone to pull thirds and eventually put it all back together for me has blown my budget a bit and truth be told, I don't NEED to do this but the bug has bit. I tried the local club to see about taking a ride in someone's similarly equipped rig who's already re-geared but that opportunity doesn't exist. So since I can't directly experience or get a close approximation first-hand, a very simple Q for this crew:

For everyone driving a 3FE-equipped, lifted FJ80 or 62 riding on 33's or bigger wheels who has already re-geared, did any of you regret it afterwards and feel it just wasn't worth the $$ once it was done and you got it back on the road?

Let's stay on topic here, thx everyone.

--t
 

SUMMIT CRUISERS Jr

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I regret that I didn't do it earlier. I too was extremely skeptical about spending all the money on something I didn't think would provide that much of an improvement. Don't expect too much around town, but highway driving is a lot better. I was actually able to merge on the highway the other day at 60 with the roof top tent on! I did 0-60 tests before and after, and it improved average by roughly 2-3 seconds. I have 33" KM2s which measure out slightly less than 32". I think 35s would give the best fuel mileage with 4.88s if you plan on driving 70+. At 60-65 mph, I have noticed better fuel mileage and that seems to be the best spot for 4.88s and 33s.
 
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33x10.50s (285/75R16) with 4.88 the second time around. I had done 4.56 gears with ARBs when I was doing a lot of commuting. My thought was that the 4.56 was a good compromise between 33s for the street and 36s for the woods. When I lost my front diff due to a stupid mechanical issue, I went 4.88s.
I've logged a lot of miles with the current setup, including 2 round trips from Jersey to Moab pulling an M416. It will never be a rocket ship, but she will cruise at 68-70 between fillups without complaint.
 
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Awesome stuff linked below. I should have noted that I've "used search" and believe I've already read most of the posts where folks who've done this in the past have positively chimed in (including the one here).


That said, the possibly counterintuitive goal here was to uncover whether anyone who'd done this upgrade had any regrets......I hadn't read any posts from anyone thru my searching/reading and no one yet has said "stay away". If by end-of-day no one stands up with a legit horror story, I'm moving forward.

THX GUYS for chiming in.........not the easiest project to commit to given its cost without being able to physically experience this personally. I know, I know........keep my expectations low and I can't be disappointed :). Your inputs are sincerely appreciated.

Sure would be funny to see a LC on the road riding on 25" tires.....

--t
 
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Cashmere WA
We offer fully built third members built by our professional installers that are a great option for those who don't want to perform installations themselves. No matter which way you go, you won't regret regearing. If you need a quote or have any questions you can give us a call at 866 349 6801 or email us at info@justdifferentials.com.
 
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the possibly counterintuitive goal here was to uncover whether anyone who'd done this upgrade had any regrets
The only regret I have is going 4.56 the first time around. 4.88 is the right choice IMO. I also did my LX450 with 4.88, but that's rolling 35s.
 
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Edmond, Oklahoma
Today I got to drive my son's 92 with 4.88's, a roof top tent and 2 bikes on a rear mounted carrier. Woohoo!:clap: This is the first time I got to drive it with the new gears for any extended period of time. Anyway, I drove about 60 miles south on I-35 bucking about a 30 mph head wind. It never downshifted and it stayed between 64 and 71 mph. As I recall the RPM's were between 2300 and 2700. This truck is definitely a whole new animal with the 4.88's. Pre-gearing, this truck would have downshifted on every incline and with a RTT and bikes on the back, I'm thinking I would have left it in third gear (never attempting the D).

As far as the install, my son and I removed the thirds, had them set up and we re-installed. I'm thinking our cost was close to 1100.00. Just a tip, don't forget to change the rear axle bearings and rear wheel seals while you are there. We found that O'Reilly's sold the Federal Mogul National bearings (part # 513008) that were actually Koyo (made in Japan) in the box for less than half the cost of the same OEM Koyo.:cheers:
 
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Gears being bought thru JD tonight and I will pick up axle bearings/seals for front and back.

I'm lucky in that ZUK lives just a few miles from me and is onboard to do the swaps. I got to spend an hour or so with him last Saturday talking shop - always refreshing to work directly with someone - great guy and he's got quite the history in the 4x4 world with more stories and magazine articles about him and his rigs over the years than I would have ever thought possible.

Now to get those thirds pulled.....
 
Joined
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Gears being bought thru JD tonight and I will pick up axle bearings/seals for front and back.

I'm lucky in that ZUK lives just a few miles from me and is onboard to do the swaps. I got to spend an hour or so with him last Saturday talking shop - always refreshing to work directly with someone - great guy and he's got quite the history in the 4x4 world with more stories and magazine articles about him and his rigs over the years than I would have ever thought possible.

Now to get those thirds pulled.....

Looking forward to seeing some pics, thanks for the business!
 
Joined
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Gilbert, AZ.
Gears showed up tonight.....time to get real. Not entirely sure what I'm in for so, keep me honest:

1. Pulling front wheels off - been there, done that when I upsized front brake rotors including new calipers/pads (first time I'd ever done that, had a few hiccups, got some help, got through it with MUCH BETTER braking power). That said, I never got into the axle - I'll go grab my FSM and start reading.

2. Rears - no clue, first time. On to the FSM.

3. Axle seals/bearings - can't remember what the recommended kit is for the fronts. I'm assuming something similar is necessary for the rears as well - suggestions?

4. I've pinged the local squad for recommendations about getting my driveshaft balanced....a bit of a wobble at freeway speeds was noticed by Zuk during some driving/discussing. Might as well do u-joints while things are apart.

5. I've read about going with bigger flanges - give me some specifics please (assuming it's truly an acknowledged good idea).

What else am I missing? This is all basically new to me, never done this type of tear down before. Not worried about getting greasy/dirty but definitely don't want to wind up over my head if it can be avoided - talk to me fellas.
 
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Joined
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Edmond, Oklahoma
Here's a few tips that my son and I learned on his regearing:

On your front, you will need a set of axle seals, wheel seals and gasket sets for sure. The bearings are usually repacked with hi-temp lithium grease and are typically reusable. For the parts mentioned above, go OEM. If your gear oil is contaminated with moly grease from the birfields, check your axle shafts for wear at the axle seal position. If there is wear (slight grooves), when you install the axle seals you may want to position the seal not as far inward (about 1/8" from bottoming out) to match up with a better sealing surface. This is assuming the original seal was installed all the way inward.

As far as the rear goes, you will need a pair of axle seals and axle bearings. I mentioned where we got the Koyo's in my post #13 above. The rear axle seals can be purchased about anywhere, you may want to stay OEM.

After removing the axles and the third member you will need to tackle the axle bearing races. First you will pry out the seals with a seal puller. Then you will need to knock or pry out the roller bearings. To get the rear bearing races out, we used a two pipe system. One piece was about 8" long that fit into the differential (pumpkin) housing and was about 2 5/8" in diameter. This was first inserted through the differential housing then into the axle tube that you want the race out. The other was about 2 1/4" ID and about 6' long that we could slip through the opposite side, match up with the larger diameter piece, then we hit it really hard to pop out the bearing race. The sizes of the pipes are estimates. I can post up closer measurements tonight if need be. The bigger pipe needs to match the OD of the race as close as possible. The smaller pipe will fit through the ID of the race. One more tip on this method, make sure you have enough room on each side of your truck to insert the long pipe.

BTW, no need to remove your rear brake cylinders and backing plates via the 4 bolts. All you have to do is push in on the axle end just enough (about a 1/16 to 1/8") to remove the c-clips in the third member. C-Clips just rotate and slide right out. Once a C-Clip is out, the axle shaft will just slide right out.

For installing the rear axle bearings, we carefully tapped them into the housing with a brass hammer. Once they started to go in, we then switched to a bearing installer kit to finish.
 
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