1G Viscous Coupler Eliminator kit

[loreak]

u dont have to, but it will help traction a hell of a lot

 

[4pistons]

You ether weld your center diff OR use a VCE. There is no point of doing both.

You can eliminate some rotating mass by using the VCE instead of the heavy VC.

As a matter of fact, unless you weld the center diff with VCE installed, the odds of it fitting are rather slim.

Boy, don't I know it!! That's exactly what I did and it was a bi*** to get it to fit back on. Took me about four hours of messing with it.

My buddy is real handy with a welder and i will be having him weld the differential for me. What specific part of the diff. needs to be welded and how strong should the weld be done?

The hardened gears need a specific method to be welded properly or they will become brittle and crack. Don't leave it for someone who just happens to have a welder. Take it to a pro, it won't cost much.

I have a diagram that shows how to weld the center diff if you want it. Email me at [email protected]

Rick - '91 GSX

 

[GRNDSM]

Originally posted by 16GTSI
ok well i am going with the welded diff for sure but do i also need a new lsd??

That is up to your budget... FWD LSD is always good to have, but at $900+ for parts and around $200 for install, it is not cheap. So not everyone can afford it.

Leon
RR

 

[Initial DSM]

Quiafe is obviously the best, but there are others that are cheaper (Kaaz). Dont know if phantom grip makes one for 4G63 though.

 

[DSM93]

Hey 4PISTONS Can I get that Diagram for the welded Diff?Im trying to decide if I should do that or go for VCE. I have an extra one and was told that there is a way to tear it apart and weld it yourself.

 

[16GTSI]

Ok i just want to make sure i am doing the right thing here. I am putting an awd tranny in a fwd car. I'm not doing the entire fwd to awd conversion, i am just using the awd transmission without any of the other awd parts(transfer case, driveshaft, rear end). I have been informed that i have to weld my center diff in order to make all power go to the front wheels. Am i correct?? Also if i proceed this way will i experience the front wheels hopping/chirping while turning? Thanks for the help guys.

 

[GRNDSM]

Yes, you need to weld your center diff. Using VCE, would still send torque through your factory 2 spider gears and is not recomended.

Driving in FWD mode would not have any more problems than what a typical FWD has. Which is not to say that FWD by nature do not have a problem .

Leon
RR

 

[4pistons]

i have to weld my center diff in order to make all power go to the front wheels. Am i correct??

Yes

Also if i proceed this way will i experience the front wheels hopping/chirping while turning?

You shouldn't because your front differential will "differentiate" the axles and allow them to turn properly.

Rick - '91 GSX

 

[Initial DSM]

my awd tranny spins my front wheels mostly is this the welded center diff mod or a broken center diff? or a viscous couple eliminator mod?

 

[4pistons]

A welded center diff or a VC eliminater splits the power equally to all four wheels. It sounds like you have a worn out Viscous Coupler that is not splitting the power front to back evenly.

Rick - '91 GSX

 

[16GTSI]

well if a welded diff send power equally to all four wheels then wont i only be sending half the power to the front wheels and the other half to the non existent rear wheels?

 

[4pistons]

When you weld the center diff the front and rear are locked together so any power going to spin the front is also spinning the back. It doesn't mathematically "split" the power a little to the front and a little to the back. If the shaft to the back isn't connected then the power is going to the front only. That's the same way an AWD car spins a two wheel drive dyno. If it was the other way, my 14B powered, daily driver would have 504 horsepower at the wheels!! WOOO-HOOOO!!

Rick - '91 GSX

 

[TalonJohn94]

Real quick question to the drivetrain experts... My AWD 5-speed has all the symptoms of a bad or welded center diff (rear wheels chirp, car gets held back while in reverse or turning slowly, strange clunking...) but after inspection, the center differentials spider gears, etc.. seem perfect. What else could cause this?

What should I check first?

 

[4pistons]

but after inspection, the center differentials spider gears, etc.. seem perfect. What else could cause this?

You sure you inspected the center diff? The trans has to be taken apart to do it. A bad center diff doesn't neccessarily have broken chunks in it. On mine the side gear spacer welded itself to the case and the side gear siezed causing the problem. You can't see it until you disassemble the center diff.

Rick - '91 GSX

 

[TalonJohn94]

Yes, I did take out the center diff. unit (took of case, gears, fork, 2nd case ~VFAQ Center Diff Rebuild ~) and removed the eight housing bolts. Like I said, I opened it and everything looked fine. I find it interesting what you said about how it could look good but be faulty. Whats the "side gear" ?

Is that just one of the 2 gear in the center diff? Spider gear?

I'll look at it more tonight and refer back to this thread.

Thanks

 

[GRNDSM]

When you removed the outer center diff cover (the one that is held by those 8 bolts). What was the condition of the bearing between that cover and the shaft that is in it?

That bearing is #1 reason why our center diff’s fail due to wear (not counting spider gear failure, which is not wear related).

Leon
RR

 

[TalonJohn94]

I'll further check the condition of the center diff tonight, the spacer, bearing etc,.. But I am starting to theorize that someone cobbed it up to be a welded center diff because that area of the transmission looks like it has been accessed once before. But I am going to look again. If everything checks out, could it be a bad VC or REAR diff?

Thanks for all your help.

 

[GRNDSM]

You can test your VC. Take outer center diff cover and place it in a vise, so that you can still install a VC on it. Then gab the VC on the outside and try to rotate it. It should move, but very slowly. Blown VCs would move with out much effort and seized VC would not move at all (mind you that out of 40-50 VCs I am yet to see one that was seized)

I was going to make a tool so that I can test them with a bending torque wrench, but I haven’t gotten around to it yet.

Leon
RR

 

[TalonJohn94]

Ok, great. That'll really help me narrow down my problem. If it is bad, would it cause the same symptoms of a bad center diff?

Have you ever had a bad rear LSD? How did you know by driving?

I am going to check everything out again tonight.

 

[GRNDSM]

VC (center or rear) usually fail by loosing their “viscous” quality, so as they fail your diff becomes an open diff. What you are describing, sounds like a locked diff (just the opposite), so while it is possible for VC to lock-up, I just never seen it.

The most common reasons for center diff to lock are: broken spider gears (you already said that isn’t the case) and failed bearing that I mentioned earlier. Shep is now offering Torrington bearing upgrade for that common failure. This picture http://www.shepracing.com/pictures/bearing.jpg shows you the new, upgraded bearing and where the old one failed. This http://www.shepracing.com/pictures/housing.jpg shows the failed housing. Anyway, those two fail, they often fuse together, creating welded center diff effect, with perfectly looking spider gears. Common cause of such failure is being towed by 2 wheels. I have seen them fuse together in less than ¼ mile of towing…

Leon
RR

 

[TalonJohn94]

Ok, I am going to look at all these things in like an hour when I get off work. Would I send Shepard the part that the bearing gets installed on? Does this bearing prevent the housing failure you mentioned?

Ok lets see, I'll check..

side gear bearings
both parts that you pictured
the VC for no spin or free spin

Great I'll try..

Thanks for all the help, I would have never got such detailed, quick help on TALK, which doesn't seem to work anymore anyway. I'll probably just PM you (GRNDSM) w/what I found so I don't distract this thread anymore..

 

[TalonJohn94]

Ok, the problem is the spacer/bearing that Shepard makes the upgrade for? Its sheared to the housing, and I will seperate it w/a press. The only question I have is if anyone knows if you send the shaft-gear part to Shepard to machine and install the Torrington bearing, or do you just order the bearing itself?

Has anyone done this yet?

 

[GRNDSM]

>Its sheared to the housing

I think that you mean that it is fused to the housing . Those parts are goners... It might be possible to separate them and then machine them, but this is hardly worth it. You will spend $100-150 on just machining and it will not be as good as before,

If you want to get yourself on the road as soon as possible, your best bet is to buy used housing, shaft and stock bearing and re-assemble everything.

Leon
RR

 

[TalonJohn94]

FUSED - That's the word I was looking for. Not to be a total cheapskate, but I have an extra center diff. out of a junk trans - in which the spiders aren't in the best shape, but the housing and bearing seem good. The shaft w/gear is in fair condition. Could I just order the shaft and a stock bearing and re-use the housing from the junk trans?

Something tells me I am going to have a hard time just ordering that bearing from my local Mitsu dealer, but we'll see.

 

[GRNDSM]

You can use spare parts from ANY center diff (so even though, ’90 diffs are different, the end-plate and the shaft on the inside is the same). However, you can’t buy that shaft by itself, it only comes as a kit with the spider gears for around $180. You should see if you can re-use your spare one.

BTW, there are two common ways to destroy that bearing and fuse the parts together:

-The most common one is being towed by two wheels,
-A more rare one is having different diameter tires (front and rear).

So what do you think caused your lock up? Whatever it was, you might want to avoid it in the future…

Leon
RR