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View Full Version : FJ40 Third Members (3.73) Wanted


baja1d
05-24-2010, 10:38 AM
I'm looking for a pair of 3.73 gears for my 40. Not really interested in trading my 4.11's just yet. I do have a pair of early course 4.11's that I can part with. Let me know. I'm in Denver 80470.

~Travis

hyperboarder
05-25-2010, 10:14 AM
IIRC these can exchange for 60 thirds, yeah? If you change your mind on swapping from the 4.11's, let me know.

Air Randy
05-25-2010, 10:18 AM
Yes, 40 & 60 thirds are identical.

Just my .02 - Why bother going from 4.10's to 3.70's? It will only make a very small difference in rpm on the hwy. If you're running any tire size over stock your performance will suffer since the gearing is higher and you're taking the engine out of it's ideal torque range.

wesintl
05-25-2010, 10:52 AM
Why bother going from 4.10's to 3.70's?

he's going to a smaller than stock tire and needs to get back to stock gearing :lmao:

Hulk
05-25-2010, 04:10 PM
Depends what you're doing with the truck. Bigger tires + 3.70 gears can make an FJ40 drive at normal highway speeds without revving the engine to crazy RPMs.

For off-road use, it would be better to go with a higher gear ratio.

Air Randy
05-25-2010, 04:18 PM
Bigger tires + 3.70 gears can make an FJ40 drive at normal highway speeds without revving the engine to crazy RPMs.

Assuming of course that the F/2F engine is in good enough shape, even with altitude derating, to maintain highway speeds with the bigger tires. Thats why keeping the motor in the proper rpm/torque range is important.

If possible, try to find someone with a similar rig with similar tire size with 3.70's in it. Either drive it or ask a lot of questions, just to make sure you will be happy with the result if you go to all of the trouble to swap gears.

DaveInDenver
05-25-2010, 04:23 PM
For off-road use, it would be better to go with a higher gear ratio.
Lots of people go 4.10 -> 4.88/5.29 -> 4.10 as their mini trucks morph through stages. The first step is make up highway gearing with 33" tires and the second step is when the truck become a trailer queen buggy and they don't care about 1,500 mile trips anymore but are tired of breaking pinions.

Personally I could seeing going down or up a single ratio, even 250 RPMs make a difference. I really want to go from 5.29 back to 4.88 for my truck. The first few months it spent a lot of time in 4WD and I loved the 5.29 gears but in the years since it's been 98.3% commuting and shuttling to St. Louis and back a lot, so I am tired of the extra couple of hours it puts on that trip.

nuclearlemon
05-25-2010, 05:11 PM
might be issues with flanges. if you get round flanges, you can drill holes to match your driveshafts, if not, see if you can get the slipyokes from your driveshafts and just swap them onto your shafts.

baja1d
05-26-2010, 06:37 AM
Thanks for everybody's input. Here's the plan that may answer a few questions. The FJ is a '64 and IMO in pretty good shape. I'd like to keep the stock look but make a decent daily driver. My commute is roughtly 60 miles and 1/2 of it is through the mountains here in CO. I'm in the process of swapping axles as we speak to 1976's. So here's what else I plan to do:

1. 33" Tires
2. 3.70 Gears
3. 4-speed tranny
4. Keep 3-speed T/C but add an Orion if I can- Anybody know?
5. 2" lift w/ shakle reversal.
6. Add power steering
7. Drive the "F" until it dies and then swap in the "2F" I'm rebuilding.
8. Lock front and rear w/ ARB's
9. Add a full cage, seat belts, ARB style bumpers, and a winch.
10. Might put a soft top on.

So much for the stock look!!! Currently the she has a "home paint job" that kept the rust down but looks crappy. Once I've made the modifications I'm sure I'll be out of money. I'm hoping to drive her for awhile and work out the bugs. Once the FJ fund has been "refunded" I'd like to tear her down and do a frame off resto. Let me know what you think, all opinions welcome!!!

hyperboarder
05-26-2010, 06:48 AM
^Did you see my post?

baja1d
05-26-2010, 06:59 AM
I did, do they have a website?

Air Randy
05-26-2010, 08:00 AM
Thanks for everybody's input. Here's the plan that may answer a few questions. The FJ is a '64 and IMO in pretty good shape. I'd like to keep the stock look but make a decent daily driver. My commute is roughtly 60 miles and 1/2 of it is through the mountains here in CO. I'm in the process of swapping axles as we speak to 1976's. So here's what else I plan to do:

1. 33" Tires
2. 3.70 Gears
3. 4-speed tranny
4. Keep 3-speed T/C but add an Orion if I can- Anybody know?
5. 2" lift w/ shakle reversal.
6. Add power steering
7. Drive the "F" until it dies and then swap in the "2F" I'm rebuilding.
8. Lock front and rear w/ ARB's
9. Add a full cage, seat belts, ARB style bumpers, and a winch.
10. Might put a soft top on.

So much for the stock look!!! Currently the she has a "home paint job" that kept the rust down but looks crappy. Once I've made the modifications I'm sure I'll be out of money. I'm hoping to drive her for awhile and work out the bugs. Once the FJ fund has been "refunded" I'd like to tear her down and do a frame off resto. Let me know what you think, all opinions welcome!!!

You'll be lovin' those 33's & 3.70's on the down hill grades and hatin' em on the uphill run and you grind along in 2nd gear. Especially after you add another 5-600 lbs of weight with a full cage, bumpers & winch. The upside is, the old 3.9 F motor will probably die a little sooner and you can go to the 4.2 2F :D. I would definitely put the 33's on it with the 4.10's first and try that setup before changing the gears. Then, if that setup works OK, try to borrow a set of roller 35's and just drive your usual route with those. 35's w/4.10's will be close to the same setup as 33's and 3.70's. Make sure you'll be happy with it. Changing gears is sort of like getting a tattoo. You're basically stuck with them once you have them, you can get rid of them later but it's a lot of work and expensive :D

Dr. Schlegs
05-26-2010, 08:25 AM
Don't forget the 4 wheel disc conversation. Major improvement is stoping power and repairs are easier.

hyperboarder
05-26-2010, 09:20 AM
Lol, I think you saw the wrong post. I'll trade you my 3.73's for your 4.11's if you want. I do know a guy who has a whole pile of 3.73's though if you're still against getting rid of the 4.11's.

wesintl
05-26-2010, 09:37 AM
Don't forget the 4 wheel disc conversation. Major improvement is stoping power and repairs are easier.

I had better stopping with my rear drums than rear disks. IMHO not worth the upgrade. IMHO it's a case of mibs.

Air Randy
05-26-2010, 09:51 AM
I had better stopping with my rear drums than rear disks. IMHO not worth the upgrade. IMHO it's a case of mibs.

Then they must not have been set up right. If you don't go to a large diameter master cylinder after putting on rear discs they will be weak.

I have rear discs on both the Mule and the Gecko, they will boh put you through the windshield if you nail the brakes. They also work great when crawling down steep ledges, etc. They never fade when they get hot or wet.

I do agree though that properly setup drum brakes still work pretty good for non-extreme offroad conditions.

hyperboarder
05-26-2010, 11:59 AM
Found a set of 4.11's, so I might have some 3.73's after all. PM me if you're interested with an offer.

wesintl
05-26-2010, 12:21 PM
Then they must not have been set up right.

don't worry they were set up right. :rolleyes:

If you have properly function rear drums I don't see need unless your building a highly modified rig.

Problem is most cyl are leaking, not adjusted etc. not to mention mibs. then they work better. otherwise it's a waste of $ on mild rig.

rover67
05-26-2010, 03:25 PM
my rear drums stop my 60 just fine...

Air Randy
05-26-2010, 03:42 PM
I'm sure they do, I never said drums were bad. I said disc brakes are better about not fading from heat or from getting wet.

Hulk
05-26-2010, 05:10 PM
So here's what else I plan to do:

1. 33" Tires
2. 3.70 Gears
3. 4-speed tranny
4. Keep 3-speed T/C but add an Orion if I can- Anybody know?
5. 2" lift w/ shakle reversal.
6. Add power steering
7. Drive the "F" until it dies and then swap in the "2F" I'm rebuilding.
8. Lock front and rear w/ ARB's
9. Add a full cage, seat belts, ARB style bumpers, and a winch.
10. Might put a soft top on.


I have a very similar setup on my 1981 FJ40:
1. 33" Tires
2. 3.70 Gears
3. 4-speed tranny
4. original 4-speed split T/C
5. 4" lift
6. Saginaw power steering
7. original 2F
8. Lockright in the rear
9. Front cage, Cool Cruiser HFS front bumper
10. Soft top.

You're welcome to come drive it to see if you like the set up.

You'll be lovin' those 33's & 3.70's on the down hill grades and hatin' em on the uphill run and you grind along in 2nd gear.

I disagree. I can keep up with traffic just fine in 3rd gear going up hills.

I would definitely put the 33's on it with the 4.10's first and try that setup before changing the gears.

This is a good idea. If you know you want 33's, getting them first is an easy test to determine if you really want to go this distance on gears. If not, you have saved yourself some cash.

Changing gears is sort of like getting a tattoo. You're basically stuck with them once you have them, you can get rid of them later but it's a lot of work and expensive :D

Great comparison. This would look good on a t-shirt!

baja1d
06-04-2010, 09:03 AM
Thanks for all the replies. I think that I'm going to try some 33 or 34" tires and see how that does before swaping gears.

rover67
06-04-2010, 09:17 AM
I'm sure they do, I never said drums were bad. I said disc brakes are better about not fading from heat or from getting wet.


I've drivin it pretty hard and never had fading issues....

they dry pretty quickly...

but yeah, disks are probably still better overall, but not better enough that i'm going to rip off what works and put them one. That's just my experience though..

Air Randy
06-04-2010, 09:23 AM
I agree, if you have drums and they work good then keep them. But, if you need a major rebuild of your brakes and the cost to rebuild drums or convert to discs is roughly the same, then I would recommend converting to disc.

There is a reason every car and truck manufacturer have gone to 4 wheel disc brakes almost exclusively: They work better under adverse conditions and they last longer and can go more miles before requiring service.