I had an '89 B2200 for 21 years....in fact, my '98 Ranger replaced it.
The tranny in your Mazda is an older version of the one in the Ranger.
The 5 speed is known as an M5M-D
Ratios are 3.622/2.186/1.419/1/.858
The auto tranny in your truck is a 3-spd w/OD and is known as N4A-HL
Ratios are 2.841/1.541/1/.72
Both tranny's connected to a Mazda "P" (as in "P"assenger car) rear axle with a 3.91 ratio.
With the 5-speed, the truck seems to perform best at 50 mph in 5th.
If you wanna hot rod your truck, the options are endless, but I wouldn't use either of these tranny's. Use something that was made to sit behind the engine you want to use.
If its a Ford, throw a C4 or a C6 behind it. If its a Chevy, one of the hydramatics would be a far better setup....same goes for the rear end.
Think hard about this and plan it all out before you touch one wrench.
If you decide to keep it stock and go another way for your hot rod, one thing you can try with your auto tranny, if you haven't done it in a while, or never have, is a filter service.
Quite easy, although a bit messy.
Grab a big flat catch pan and set it under the tranny.
Pull all the small bolts on the bottom that hold the pan on the tranny.
Take care because its full of fluid. If you can, try tip one end down and drain all the fluid into your catch pan.
Once the fluid has been drained, set the tranny pan next to you and remove the large filter sitting on the bottom of the tranny (its bolted on, to some degree. Look around before putting a wrench to it).
Reverse the procedure, to install the new filter.
Remove the old pan gasket and clean the mating surfaces, then install the new pan gasket (a light application of Permatex or even grease, will help you here).
Reinstall the pan and tighten the bolts.
Put the truck back on the ground and pull the tranny dipstick and set it to one side.
Place a funnel in that tube and pour the appropriate amount of the appropriate tranny fluid in through the tube (via the funnel).
Once you've done that, jack up the rear end of your truck and place the rear axle on jack stands (set the stands on their absolute lowest setting. You only need to get the rear tires off the ground. Doesn't have to be too high to do that).
Block the front tires and start the truck. Shift the tranny into drive and watch for the rear wheels to turn.
Once they do, put on the brakes and shift into reverse then left off the brakes. Watch for the rear wheels to turn.
Do this a couple more times, then put the tranny back into park and put the back tires back on the ground.
If everything looks like its working like it should, take the vehicle out for a short test drive. Give it enough time for the engine to fully warm up.
Once you're back home, pull the dipstick and check the level. Add more fluid if necessary.
It's important to have the vehicle warmed up before checking the level of the tranny fluid, as doing it cold will give you a false reading.
If everything's gone the way it should have, congratulations, you've just performed your first tranny service.
The reason I'm walking you through all of this is because what your experiencing could be lack of fluid flow through the tranny due to a clogged filter.
The fluid may have also thinned through age and use, to the point to where the tranny doesn't quite operate like it should.
While this may, or may not, fix your problem, it is the easiest and least expensive "repair" you can make to the transmission. Any mechanic will recommend it as a "first step" towards making your tranny work properly.
If you do this and there is no change in how the tranny performs, there may be a deeper problem. At that point, you're likely looking at a total teardown and examination.....and this is where things get REAL pricey!
Try the service first. It'll probably put things back right. I just can't gurantee that it will.
As for a service schedule, I've never heard or read of any, but the new fluid and filter should be good for a few years of driving, at least.
Dean
P.S. If you're curious about the specs for your 1991 Mazda truck, I think you'll find this page quite informative -
http://www.mazdatrucking.com/B2200/B22Specs.html
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