98 Mazda rear differential

[jhigh]

I have a 1998 Mazda B3000 4x4 with a bad rear differential. I know this is a Ford Ranger differential, but th rangers came with a 7.5 and a 8.8 3.73 ratio. My door tag code is a F6 axle code.
The tag on the differential is gone of course, can any one tell me weather this is a 7.5" or a 8.8 " ?
I need to get a used differential from a salvage yard and dint have enough information to answer all there questions. I need to know if this is a 7.5 or a 8.8

[crank.it]

hi j-the only real way to be 100% is to take off the rear cover and find the ratio stamped on the diff gear...crank.it

[jhigh]

(01-04-2011 09:43 AM)crank.it Wrote:  hi j-the only real way to be 100% is to take off the rear cover and find the ratio stamped on the diff gear...crank.it

I was hoping that some one could tell me what size ring gear this is, the rear end is looked up and going to be a hassle to get in the garage.
I wanted to have every thing i needed to change this diff before I get it in the garage. Very cold outside. LOL.
I know that the ratio is a 3.73, from the front tag, the rear tag is missing.

[jgate]

OK that Mazda F6 code does state that this is a 7.5, 3.73 ratio
differential. You could just take a few seconds and measure the backing plate, you cant put a 8.8" ring gear in a opening that is only 8.25".
Or an easier way is to check out the attachment and look closely at the top of the backing plate, you will see two cut outs on the top of the plate, this is an 8.8- 3.73ratios, differential. On the attachment, of just the plate itself you can easily see the cut outs at the bottom of the plate. If you don't have this design of backing plate then you have the 7.5 ring gear.
Hope this helps..

[jhigh]

I forgot that you have to be signed in to view the attachments full size.
well any how with the pictures you posted of the 8.8 differential , and measuring the housing it being only 8 1/4" , to small for the 8.8 ring gear.
I must have the 7.5.
Now I have to see if I can find one from a salvage yard.
Thanks a lot !!

[jgate]

OK now that you have determined that this is a 7.5" and a 3.73.
There are still 3 different 7.5 differentials for the Ranger/ Mazda, There is the "open" the limited slip, and the locker differential.
according to the F6 code you will need the 7.5 limited slip differential. and they had two different brake sizes , 9" and the 10".
You could use either one if you might be open to buying new set of brake shoes and hardware.

[jhigh]

I did find a locker 7.5,. You said by the code that it should be a limited slip differential.
The locker is almost a couple hundred dollars cheaper than the limited slip , can I install the locker , with out any modifications?

[jgate]

As long as the year is between 96 and 2000, there should be no modifications that would have to be done , should fit right in.
I don't know if this your truck or a customers.
The drivabillity of this truck will change, Automatic lockers transmit power to each wheel through a pair of dog clutches. Differential action such as when cornering is provided by automatically disengaging the appropriate clutch when one wheel rotates faster than the other, This results in differential action which occurs in ratcheting stages rather than being smooth and progressive. Power received by the differential is automatically directed to the wheel with greater traction. Therefore, if one wheel is lifted off the ground, the other wheel will receive the total power.. Traction is superior to conventional and limited slip differentials. While automatic locking differential provide improved performance off road,, vehicle handling, particularly on highway,, is sacrificed.... Unlocking during cornering can be sudden,, resulting in a rapid change of direction, particularly in short wheel based vehicles. During sharp cornering an audible ratcheting sound usually occurs as differential action takes place and a loud banging noise may be heard when the unit locks up again. And tire wear is usually increase On 4WD vehicles....

[jhigh]

I referred your concerns to the customer, and he agreed to go with the locker, so we put it in and the truck has been gone for 2 days so far and so far no complaints, I will keep you posted of any problems in the future.
thanks a lot for your help.