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cartman
07-01-2003, 10:58 PM
hey guys i jsut found out i have a 3.73 LSD in my parts car :) is this rare? its an 82. so now i have a 4.3 a 4.1 and a 3.73. is it a good idea to swap this into my 86 (4.3). my 86 whines and howls all the time. will the 3.73 bolt right up to my 86??
sloopercat
07-01-2003, 11:17 PM
If you want to stick with the 4.3, for power reasons. I will swap a perfectly good tight no whine 100K 4.3 LSD out of my 84 for your 3.73. I am going 7MGTE so I don't need the lower gearing for acceleration.

Yes, any of the diffs are interchangeable, but to get the speedo working with your 3.73, you are going to need to dismantle the back half of your tranny to swap gears.
SupraFiend
07-01-2003, 11:19 PM
its standard on 5spd 82s, so its only as rare as 82s are, which are actually starting to be kind of rare. Yes the whole diff from your 82 will bolt to your 86, the question is what kind of shape is the diff on your 82 in? If its got over 200,000kms it might not be any better then the one on your 86. The 3.72 will give you great gas milage (on the highway at least) and make your car feel really slow around town. You'll have to swap the speedo gear on the tail shaft of your tranny too.
SupraFiend
07-01-2003, 11:23 PM
Simulpost! He hes near Vancouver, the shipping on sending a whole pumkin each way would be crazy, and he doesn't really have any incentive to take just the diff out.
sloopercat
07-01-2003, 11:36 PM
Double post! I really only want the gears. I have another complete truetrac diff, we can maybe make a deal if the gears go one way and the complete diff goes the other.

BTW, you can get brand new 3.7~ gears from Toyota. I have not heard of aftermarket ones. Anybody else?
SupraFiend
07-02-2003, 12:16 AM
thats what I've decided to do. I've pretty much given up on finding a 3.72 diff in the condition I want, I want a slick brand new feeling diff, no more clunking. Hopefully I can find an alternate supplier for the ring and pinion gears.
82Spearco
07-02-2003, 12:57 AM
If you want to upgrade to the Tru-trac, Sean at River City Diffs can supply with the whole kit and caboodle! All you have to do is install it when it arrives.
sloopercat
07-02-2003, 08:31 AM
Are you saying that Sean can get aftermarket 3.73 gears? I already have a 4.10 trutrac diff built up in the box. Can you get me his #?
SupraFiend
07-02-2003, 12:01 PM
yeah what he said, most places that sell the lsds don't sell the ring and pinion gears with them.
82Spearco
07-02-2003, 05:50 PM
I will have to go back through the posts, but I am pretty sure that Jim King sent a ring and pinion gear to Sean for his Tru-trac, but that someone else had Sean provide everything. Sean has a supply of parts compatible with ours, mostly from the front 7.5" diffs from toy 4x4's. Maybe I am wrong......

Maybe Jim, Don, William, or someone else who has gone through this process will chime in.
sloopercat
07-02-2003, 06:46 PM
Lowest numerical ratio aftermarket I have seen is 4.10. The 3.72x7.5 had such limited applications.
SilverMk2
07-02-2003, 09:19 PM
Sean said he had tons of 3.73s sitting around. He said he usually has a hard time finding 4.10 and 4.30s. You can still get new 3.73 gear sets from Toyota. I believe the were like $525 special order from Japan thru Jeff.
SupraFiend
07-02-2003, 10:00 PM
ouch, must find aftermarket replacement....
sloopercat
07-02-2003, 11:14 PM
I will call Sean tomorrow, thanks for the info. I also see a lot of used 3.73 diffs on the internet part searches for $100-250. Would rather have one in someone's hand that knows what's what.
WadeT
07-17-2003, 01:37 AM
One thing, if you swap that 3.73 into your 86 the speedo will nolonger be accurate.
SupraFiend
07-17-2003, 10:57 AM
....until he swaps the speedo gear on the tailshaft housing too you meant to say, right :wink:
jdk_ii
07-17-2003, 08:49 PM
I will have to go back through the posts, but I am pretty sure that Jim King sent a ring and pinion gear to Sean for his Tru-trac, but that someone else had Sean provide everything. Sean has a supply of parts compatible with ours, mostly from the front 7.5" diffs from toy 4x4's. Maybe I am wrong......

Maybe Jim, Don, William, or someone else who has gone through this process will chime in.

I sent the ring and pinion. He had an extra carrier. It was less expensive
than shipping the entire carrier.

Wondering if Richmond Gear would be interested in making another
3.72 ring and pinion production... (would require some high numbers..)