Lack of Fill Port on Differential Cover after Servicing at Garage

Honestly? I don't care. The last time I checked fluid in the rear was my '53 Mercury. I've never had a differential problem with any care I've ever owned and I've never changed the fluid in any of them.

Only time we pulled a differential was swapping my brother's 4.56 Posi Traction for a 4.11 and fifty bucks. That was in 1962 or so.

If the fluid was changed a few years ago, it will probably last another 25 or so.

Your vehicle is a Ford. The fill hole is in the front.

What if it's a limited slip diff. i'd change fluid often.

Yes, we did that in 1962.

Every 25 years or so seems to be good.

My brother was a car collector and restorer and owned about 20 to 25 cars at any given time. Unless it had to come part for some other reason, differential fluid was usually never changed. Even on his '69 Impala with 350,000+ miles. That was his daily driver until he sold it in 2002.

GM shop manual for my '99 Yukon says change rear end lube at 30k miles. When I did at 35k it looked like it needed a change, like it badly needed a change, refilled with syth. and when the dif. cover rusted through at 90k lube looked way better that the factory fill. Oils wear out, no matter what component they are in, I've had my share of diffs break / wear out.

Ya, I agree. The oils do need changing regular. I just replaced the u-joint= and got a good look at the front bearings on the differential. Now there's= a work of art. Fortunately the gear oil was good. That rear end has over 4=

00,000k on it (don't know what that is in miles) and so far only had to rep= lace the two axel wheel seals. Guess it depends on what type of oil is in t= he rear axel to begin with. But oil is still cheaper than parts, well it us= ed to be.