Topic: 80 4X4 Next mystery 4.88 Rear Diff (SOLVED FOR NOW) thanks

[69800]

Now I need a new rear diff and I would like to get a complete 3rd member.

1 Mystery ONE.. I counted my drive line and came up with 4.8 revolutions.. I do not see a 4.88 ever being used in 79-83. Am I to assume some one stuck in a 4.88???  I am turning 3500 rpm at 60 with 30 inch tires. Sound right?

2 Mystery TWO .. Does anyone know of anyone who sells toyota 3rd members with 4.88's

3 Mystery THREE  Is it possible to get a clutch type posi traction for this rig??

thanks
mark

[MC387]

Just about any toyota vendor can sell you a complete diff set up with 4.88's.  Or you could buy new gears and have  a local shop set them up.  Or you could find a 90's runner with an automatic, some came with 4.88's.  I wouldn't waste your money on the clutch type LS.  Get a locker.  Get a selectable if you dont want a locker on the road.  At the least get something like an auburn, but they are very pricey, and you will be soarly dissapointed the first time you get into the rocks.

[Rocksurfer]

I loved my Auburn's but locked is best. I ran Auburn's/Downey's in my 80 always did well never had any trouble. Have to admit though I would have preferred at least one locker like I did in my 84, ran a Detroit in the rear and an auburn up front.

[Sparkplug]

I would just go to a junkyard, and get 2 4.10 difs if you have 30 inch tires, would be cheaper than 1 4.88 I would assume. I could get 2 in my town for 100 bucks. Also about the locker. Myself, Id just get it welded up. But if you want something that unlocks, I had an aussie and it was great offroad, and livable in town.

[69800 [OP]]

I hate buying junkyard third members. I never know what Im into. This is a daily driver not a rock crawler. I live in snowy idaho and can probably get by with out the limited slip or lock up. Plus I am retired so I dont really have to go anywhere. I have a ford and a chevy 4x4 and a subaru. I got this truck for my dog.

[pumkin toy]

I got this truck for my dog.

your dog knows how to drive?.....

[kneedownnate]

1 Mystery ONE.. I counted my drive line and came up with 4.8 revolutions.. I do not see a 4.88 ever being used in 79-83. Am I to assume some one stuck in a 4.88???  I am turning 3500 rpm at 60 with 30 inch tires. Sound right?

3 Mystery THREE  Is it possible to get a clutch type posi traction for this rig??

thanks
mark

1 - you most likely have the stock 4.37 gears.  I have a 4.30 in the rear since I kept breaking the 4.37 rears, and I turn about 3300 rpm at around 70 mph.

3 - not likely, posi is a gm limited slip    You can get at least a couple different limited slips, or you can get a v6 or turbo rear 3rd, pull a limited slip out of a supra with g code gears and install it in the 3rd.

[69800 [OP]]

I turn 3500 at 60 so I am probably 4000 at 70. This has to be a lower ratio that 4.37
mark

[pumkin toy]

I turn 3500 at 60 so I am probably 4000 at 70. This has to be a lower ratio that 4.37
mark

you guys might have different size tires too.  there are alot of things that affect the rpms

[69800 [OP]]

Tires are 30 x 9.5 x 15

And remember its a 4 speed until I get the L52 in. I think that will drop the rpm down about 250 rpm

3 - not likely, posi is a gm limited slip  Gap  You can get at least a couple different limited slips, or you can get a v6 or turbo rear 3rd, pull a limited slip out of a supra with g code gears and install it in the 3rd.

WAIT A MINUTE  Are you telling me they had limited slips in supras and v6's? What years will fit?? I was under the impression that 1995 and below is my limit of years

Ive been told auburns are no longer availible. Aussie looks like a pretty nice unit but I was hoping I could get by for less money.


mark

[H8PVMNT]

I have an '80 with the 4.37s and I turn about 3900 at 70 mph.  With the 4 speed these trucks are really low geared on the highway. You probably have the 4.37s.  With 4.88s you would probably be turning more like 4500 at 70. If you really want to know drop out a third and count the teeth on each gear, then divide.  Also I would not hesitate to slap spme use third members in the truck.  You can tell pretty easy if everythings tight and it will save you like $1,000 if you plan to have a shop set up  gears for you.  With the money you save you could buy aussie lockers for both ends.

[NorCalToy]

I turn 3500 at 60 so I am probably 4000 at 70. This has to be a lower ratio that 4.37
mark

using a converter on http://pitbulltires.com/calculate.php you would have to have 5.29s to turn 3500RPM's at 60 with a 30" tire


Use the calculator for finding MPH enter in your ratios and then modify the axle ration until it reads 60MPH

A 5.29 would read 59.07 which is the closest to 60 i got with a different than stock gearset.

[8D3TOY]

Craigslist is your best bet, or the classifieds on here but shipping will kill a good deal.  If you could get a junkyard 3rd put it up front and swap your front to back.  Even a 1980 front third will have low miles on it.  It is pretty hard to count out the difference between 4.37 and 4.10 odds are you have factory gears 4.37 and a 30" tire is not actually 30" tall combined with the 4spd your RPM could be significantly higher than calculated.

[79coyotefrg]

using a converter on http://pitbulltires.com/calculate.php you would have to have 5.29s to turn 3500RPM's at 60 with a 30" tire


Use the calculator for finding MPH enter in your ratios and then modify the axle ration until it reads 60MPH

A 5.29 would read 59.07 which is the closest to 60 i got with a different than stock gearset.

using http://www.4lo.com/calc/gearratio.htm and assuming his 30-950-15's arent aired up to 60 psi so they will squat a touch i pout in 28inch tires, 3500 rpm, 60mph 4th gear 1:1 and guess what it turned up 4.88

you SHOULD have 4.37's gear code G102,  BUT some 80 models came with 3.90's gear code G072,  if so its extremely possible someone installed 4.88's

follow this link for the best differential you can buy  http://www.marlincrawler.com/differential/complete

[69800 [OP]]

I will measure the tire and/or pump them up and run again with the gps. I will see if it will go 70 also

[69800 [OP]]

I meaured the tires .....29 inches tall...
I counted the driveline with 20 tire rotation  48 and 1/2 revolutions = 4.88 gears in the diff.
speed test coming after breakfast

[kneedownnate]

you guys might have different size tires too.  there are alot of things that affect the rpms

  sometimes thoughts don't make it from the brain to my posts.  I meant to say I have 33s.  The site blake linked is interesting, but I have to question it a little.  There's almost always a difference between indicated and true speed, especially in vehicles several years old or older.  If you ever get to pass one of those digital speed signs you can peg it down.  My 91 2wd came with 195/75-14 and I knew it read fast but had no idea how bad till I installed the mustang wheels with 215/65-16 and repeatedly passed the digital speed sign and it was either dead on or 1 mph off    That's a lot bigger tire than the stocker, so you can imagine how off it was before!

Also, according to that site I'll be spinning 2627 rpm at 60.  I'll have to double check it to see what rpm I should be turning at 65 and 70 mph and test run it to see how far off it really is. 

I'd make a run past it in the 4by to see how far off it is, but it's about 15 miles up the road from me and my truck gets crappy gas mileage.  Wasn't a big deal when I only worked a couple miles down the road from it.

[H8PVMNT]

Sounds like you do have 4.88s.  Want to trade for some used but good 4.30s I have laying around?  I can deal with the buggered used gears...  I'll ship mine and you ship yours.

In all honesty the most cost effective route for you would be to find a good used 4.88 third from a '94 or '95 4Runner automatic.  I know a guy who probably has one.  Wolff Auto... (406) 273-7213

[69800 [OP]]

I am surprised that that new of 4 runner fits the older toyotas. are the limited slip? Is there a web site for what 4 runner stuff fits the older toyotas?

[H8PVMNT]

You can use the rear thirds from a '95 or older (before they changed to the tacoma style) 4Runner as they are just a 8" Toyota diff like your pickup.  The one you want with the 4.88s will have the 4 pinion V-6 diff.  You can use a lock rite or an aussie locker in those if you want to upgrade.  I don't know about a limited slip for those but I'm sure they make one...  Call that guys number he'll straiten you out on what fits even if he doesn't have the parts.

[79coyotefrg]

I am surprised that that new of 4 runner fits the older toyotas. are the limited slip? Is there a web site for what 4 runner stuff fits the older toyotas?

any 8 inch aka G axle code, differential up to and including 95 will bolt right in to your housing

[79coyotefrg]

Now I need a new rear diff and I would like to get a complete 3rd member.


2 Mystery TWO .. Does anyone know of anyone who sells toyota 3rd members with 4.88's

um  the same guy who owns this forum  --> http://www.marlincrawler.com/differential/complete

3 Mystery THREE  Is it possible to get a clutch type posi traction for this rig??

thanks
mark

clutch type, yes,  auburn is a good brand,   but to be honest a detroit true trac would be much better,  its a gear biased limited slip, aka no clutches to wear out

http://www.4crawler.com/4x4/TrueTrac.shtml


http://www.nationaldrivetrain.com/shopsite_sc/store/html/page44.html

[79coyotefrg]

http://nationaldrivetrain.com/shopsite_sc/shopping_cart/order.cgi?rd=1&storeid=*0e82f1610f6d1d0895&sbid=SSMSB1259088058.13303&prevlocation=http://nationaldrivetrain.com/shopsite_sc/store/html/d_truetrac_toyota.html

[69800 [OP]]

any 8 inch aka G axle code, differential up to and including 95 will bolt right in to your housing

Are all of these g code axles limited slip.. If so are they clutch type?

Gee, these true track, auburn, aussie are a lot more expensive than I was hoping for. Thats why I was trying to find a used factory toyota limited slip from craigslist. I dont need a hard locker just something for snow

[Stocker]

Kneedownnate here - I've never come across a factory limited slip for a hilux, at least an early one.  Only one from the factory which will work in the v6 or turbo 3rd is a supra limited slip.  The way to know if a toyota came with a limited slip from the factory is if the 3rd digit after g is an odd number, a 3 or 5.  Look in my sig line for a buildup on one.

[69800 [OP]]

back to the drawing board
mark

[69800 [OP]]

rotating the wheel 20 times with a driveline count of 48 and3/4 was right on the money. Ring and pinion count was 4.88