Would like to do a diff fluid change on my 1992 Ford Ranger XLT. Has the 3.0 L V6 with the five speed Mazda manual transmission, and just a 2WD rear axle.

When I bought the truck, it did not come with the owners manual. It’s a little hard to know what fluids and such to use, so just wondering what would be the best to use in my truck? I’m assuming something like 80W-90?

Also, how much fluid does it take, and is there any special additives I should use? Any tips on doing the change, and should I remove the diff cover and clean everything out or just warm it up and change it?

Thanks!!

 

Your diff should have a tag on it that will denote gear ratio and whether its limited slip or not. It should hold between 2.5 to 3 quarts of 80w90 gear oil. Just buy a gallon jug and fill it up until starts running out the fill hole.

Ive got a 99 4.0, manual trans, 4wd that Ive had since 2001 and have changed my diff gear oil several times over the years and I have never taken the diff cover off. Matter of fact I just changed my trucks diff fluid two weeks ago. It came out just as golden as the fresh that went back in. I saw no reason to take the cover off. I also changed my transfer case, transmission fluid, and front diff as well. Personally, I would start pumping the gear oil out and if its really dirty or you see debris or there's a lot of metal shavings stuck to the fill hole plug I would consider taking the diff cover off.

 

Thanks for the info, I appreciate it!

Here is a pic of the tag on my rear diff. Can you tell if it’s a limited slip and just also curious to know what the gear ratio is on it? Thanks

 

It's a 7.5 ring gear size. Your gearing is 3.45. From what I can see It is not limited slip. If it was it would have an "L" in between the 3 and 4