FG diff. removal

[Big Bill]

What is required to remove the rear diff. on an FG 4WD car? It almost looks like the entire car needs to be stripped to get it out, any info is appreciated . Some thing is not quite right in mine, with the wheels off the ground if I hold the rear wheels and give it some throttle the front wheels spin but the rears will spin but if you hold them tightly they don't seems to have any drive. I am thinking its the planetary gears in the rear diff.....maybe. Thanks

 

[DougStar]

Hi bill??
Is it off road or on road?

 

[AnubisBC]

Hey Bill,

Sounds like normal differential action. A lot of 4wd cars have a center differential and if it's low on oil or is filled with a light oil, you can easily get it to diff out. Do you get the same behavior if you hold the front wheels instead of the rear?

 

[DougStar]

Hey Bill,

Sounds like normal differential action. A lot of 4wd cars have a center differential and if it's low on oil or is filled with a light oil, you can easily get it to diff out. Do you get the same behavior if you hold the front wheels instead of the rear?

Fg only have two diffs front and back??

 

[AnubisBC]

Fg only have two diffs front and back

So is there a slipper clutch on the center?
Edit: nevermind. Just looked up and see FG uses a belt system, at least for the Marder and Sportsline 4WD. Interesting.

I'll leave this to the FG gurus. Sorry I can't be of any help. ?‍

 

[DougStar]

In an FG drives a gear on the rear diff
Also on the diff is the belt gear. The two gears bolt to the diff?? so either the gears have separate from the diff ( don't see this happening) or a drive cup has come out? the drive cups have splines cut into them and the just slide in. There is no grub screw holding them in. If one side is out the diff will not work.??

This is my fg diff???
This is what the drive cup splines look
Like??


And other than one pin there is nothing holding the gears in place? so the drive cup splines holding gears in place as well??

 

[Big Bill]

Hi guys thanks for the reply's I did get the rear diff. out. I bought this car used and the PO was running a one-way diff in the rear???? weird. Anyways I ordered the parts to build a conventional diff. from DDM should get me back on track.Thanks

 

[Seandonato73]

If memory serves, that should have been in the front diff to allow for better off throttle turning. Frees up the font axle when power isnt being applied.

 

[DougStar]

Glad you got sorted??

 

[Striikar]

If memory serves, that should have been in the front diff to allow for better off throttle turning. Frees up the font axle when power isnt being applied.

Yep,weird. Maybe he didn't realize the difference when it was installed.

 

[Big Bill]

Yes strange, there is a one-way in the front also. The car was OK but did weird things on track when least expecting it. Almost $200 for the stock parts to build a rear, I will replace the front this winter when I tear the car down for a complete rebuild. Thanks the the info guys.

 

[Seandonato73]

That's why, if the momentum of the car overcame the throttle input it would have coasted, then when the power came and it grabbed it would cause the car to go all wonky