FE-FC Holden Discussion Forum

 ;)

Hi guys,

Replacing the wheel bearings and oil seal in the diff on the ute. What should the ratio be. The ute centre has a ratio stamped on it 3.89. Is that good or not. The part # on the gear and pinion in the cattledog  is 7406081 doesn't match either part # on the the diff.

ideas

Rusty

3.89 is standard for all FE FC. A stockie in good order can easily run a 3.55 ratio and improve fuel economy on long runs. 3.55 ratios first appeared in the EH.

Ken

While we're on the topic,are FE and FC sedan diff centres EXACTLY the same?Cheers Jamie.

Well no not entirely, a scan through the parts book shows a change in the pinion shaft half way through FE. The lock pin also appears to be changed as well. These two items were probably changed as an improvement or upgrade. I can't see anything else different. Possibly the case casting was upgraded which would not necessarily get a new part number.

Ken

Also worth mentioning if you swap to a later diff centre (3.55) it's a different rear universal  ;)

Mick 8)

Yes thats a good point mick.

worth the effort i run a 3.36 in my stock FE good cruiser all round.

can be a little trying on the clutch but i will replace the engine and clutch soon as its age and condition are unknown

For the EH and later diffs the rear uni joint is the same as the front.

Me too.  I run a 3.36 diff in my sedan.  Maybe a little slower off the mark.  I don't have to slip the clutch any more than with a 3.89, but it's a far more relaxed cruise at highway speeds with a 3.36.

Rob

 Due to the lower tyre profiles to maintain highway speed at realistic rev.s and true speedo calibration a necessary evil

This link is always handy when changing diff centres / tyres etc.

http://www.kabamus.com/garage/gears.html

Mick 8)

is the diff housing the same in the eh as the fe or do you cange the housing as well

Apart from a few subtle differences (bearings etc) the whole lot is an interchangeable unit. So diff centers can be interchanged.
However, for a better selection of wheel cylinder sizes to suit the front brakes it is better to use a HR rear end.
Then again if you are going SBC, maybe a Borg Warner or 9 inch would be better


Ken

Hey Ken,

I have been given an EJ. Very sad but it has a 149 that runs and some other bits I thought I'd scavenge. It has a Hydramatic in it. Is the diff ratio of the auto the same as the manual because I thought I might use it in Effie. What else might be worth scavenging ?

Cheers

Mark

Stock ej auto has the same diff as a manual, but have a look, it may have been changed....

Ken