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condorjohn
10-20-2019, 08:49 PM
My beautiful 1996 Mazda b4000 blew the flex plate. I have tried to find out what the estimated cost of repair is with no success.

Any members know what the approximate cost would be, parts and labor? It ran like a top 'till it blew!

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osteodoc08
10-20-2019, 09:23 PM
Not sure on pricing, but any shop should be able to give you a reasonable estimate. Same thing as a Ford Ranger.

Petrol & Powder
10-20-2019, 09:44 PM
The flex plate is sort of like a flywheel but lighter. It connects the output of the crankshaft to the torque converter of an automatic transmission. The part itself isn't too expensive, it's basically just a big piece of stamped steel with holes in it for bolts. Some have a ring gear for the starter to engage and some don't, depends on the design.
However, getting to the flex plate requires separating the transmission from the engine. The labor is the big part of that job. If the truck is a 2 wheel drive model it's an expensive job, if the truck is a 4WD; it is more expensive.

Flex plates do occasionally crack just due to fatigue but sometimes they fail due to some other problem such as a transmission that isn't tightly bolted to the engine, a bad front bearing or bushing in the transmission or some debris in the space (like a broken nose on a starter housing).

So you will not really know until you get everything apart. Once the transmission is off, it's a good time to look at the rear seal for the crankshaft. If the engine has a press in rear seal and the engine has a lot of miles on it, that's a prime time to replace the rear seal. (also a cheap part).

I would guess the repair will be the going hourly rate and at least 6 hours worth of labor. I the truck is 4WD, I would add another 2 hours to that estimate.

redneck1
10-20-2019, 10:06 PM
I have a 98 Mazda , the transmission went out on it a few years ago.
In my driveway on Jack stands it took me about 5 hours to swap it start to finish .

A good shop with a lift should be able to beat that by quite a bit.
I'd hesitate to take it to a shop that doesn't give you an estimate under $500.

Petrol & Powder
10-20-2019, 10:06 PM
And I just looked up a flex plate on NAPA's webpage and they sell it for $70.

Petrol & Powder
10-20-2019, 10:12 PM
I have a 98 Mazda , the transmission went out on it a few years ago.
In my driveway on Jack stands it took me about 5 hours to swap it start to finish .

A good shop with a lift should be able to beat that by quite a bit.
I'd hesitate to take it to a shop that doesn't give you an estimate under $500.

In a shop with the proper lift and a transmission jack, I could do that job in way less than 3 hours. BUT, most shops will not price that job like that. They will pad that time estimate and mark up the cost of the parts.

megasupermagnum
10-20-2019, 11:31 PM
I happen to be an authority on old ford/mazda ranger based vehicles. I currently own a 1993 explorer, 1994 explorer (parts truck, used to daily drive), and daily drive a 1994 mazda B4000. Also have experience working on various ford rangers and bronco II. I'm familiar with the full size Fords too.

Unfortunately I believe you will have to pull the transmission to replace the flex plate. On transmissions with a removable bell housing cover, you can sometimes get away with just pulling the tranny back for enough room. Being a solid cast and integral bell housing transmission, you will have to remove it. The M5OD-R1 manual transmissions are quite easy to deal with. All of the auto trannys are a bugger. The two biggest problems are the cooler lines and the torque converter bolts. I would assume there is a special tool for the torque converter bolts, but I don't have it. You can do with with a box wrench, but it is not enjoyable at all. The cooler lines are a lot easier to take off, and a real PITA to get back on. The bell housing pattern is... well it's ford. The trick is once you have the driveshaft, transfer case, and crossmember removed, let the transmission hang down. Then use a 3 foot extension, or a bunch of short ones together, to reach the top bolts. The starter is easier than it looks. Then there is actually removing the transmission. I'm young, I just bench press the light trannys like this no problem. Speaking of which, the transfer case seems just as heavy as the tranny! I'm not sure how most people do it. I replaced the clutch in my B4000 this spring. I've got it down to an art, and it's still a 5 hour job if you include clean up, and that's the much easier manual transmision.

I would think most shops would quote 6 hours for this job. I wouldn't do the job myself for you for under $500. I would think you are looking at $800+ at most shops, plus you tack on anything else wrong. I've never worked as an auto mechanic, but I do not know what is included with a broken flex plate. Are the teeth stripped off for the starter, or did it actually break? I know they can crack, causing a ticking sound, if they work at all.

One thing with the 4.0 OHV engine is often by this age the rear main seal is leaking. It's not a huge deal to replace with the transmission out, and is something to consider. That said, mine leaks, and I still opted not to replace it. Mine just passed 300,000 miles in August. Never mistake it with the 4.0 SOHC, which is a disaster of an engine, and destroyed the reputation of these old fords.

condorjohn
10-21-2019, 01:03 AM
This truck has 180K on it. Does not burn or leak oil or tranny fluid. I asked about this here on the forum to get an idea if it is worth fixing. From what all y'all said I think fixing it is the way to go.
Thanks, John

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abunaitoo
10-21-2019, 02:10 AM
Nice looking truck.
Looks to be 2WD.
If it's 180k highway miles, it's not a problem.
If it's around town, stop and go millage, trans might be going.
Kind of hard to tell, but if the price is right, I'd pick it up.

redneck1
10-21-2019, 02:41 AM
My little truck is a piece of rusty junk , but the brakes work good , the tires are still round and it runs like a top .
The transmission in mine was a known issue when I bought it so I don't consider it a " breakdown " .
And otherwise it has been a good truck just like the Other two rangers I had .
But if and when my well used vehicles break I try to keep things in perspective.
Anything under $100 I just fix without a second thought .
Anything over that I think in terms of what another vehicle is going to cost me .
So if say the repair bill is $500 that's roughly a car payment and some change for the next one .
If I'm reasonably confident that the vehicle will last at least that long after its fixed I just go ahead and fix the thing .
Any time it lasts after that is just icing on the cake to me .

So if it otherwise runs good and it won't need Any Other money dumped into it In the near future I'd for sure fix it over replacing it .

Screwbolts
10-21-2019, 06:37 AM
here are the flexplates, Rockauto

https://www.rockauto.com/en/catalog/mazda,1996,b4000,4.0l+v6,1190720,transmission-automatic,flexplate,8608

Screwbolts
10-21-2019, 06:43 AM
Being your 4K is 2 whl drive changing the flexplate will be a piece of cake. No heavy useless transfer case hanging from the transmition or front drive shaft to deal with. Removing the transmission isn't a big deal. look up online the torque for the bolts used to attach to the crank and torque converter and have at it!

Ken

Petrol & Powder
10-21-2019, 08:35 AM
Being your 4K is 2 whl drive changing the flexplate will be a piece of cake. No heavy useless transfer case hanging from the transmition or front drive shaft to deal with. Removing the transmission isn't a big deal. look up online the torque for the bolts used to attach to the crank and torque converter and have at it!

Ken

Well, I've done that job and it's not horrible but it's not a "piece of cake" either. 2WD is certainly easier than 4WD.
I appears the OP is seeking to pay someone to do that job. I would be surprised if a shop quoted that job at less than 6 hours. That doesn't mean it takes 6 hours , that just means they will quote 6 hours.

And fixing that truck is certainly worth it.

Jniedbalski
10-21-2019, 09:45 AM
It’s a easy fix if your young. Had a dodge van that cracked a flex plate at work. It was a Ac repair shop. The boss asked if I could fix it. Well at 21 I could fix About anything growing up in my grandpas body shop. In 5 hours including 1/2 hour for lunch it was back together and running. Told the boss it’s done and he didn't believe me it went so quick. No trans mission jack just bench pressed it up and had the other guy put the bolts in. Very easy when your young

EDG
10-23-2019, 03:24 AM
If your transmission has a lot of miles you could have it rebuilt by a transmission shop.
They will pull the transmission and they can replace the flex plate in 20 minutes.
I had a flex plate break on a 4WD Suburban and it squawked like a dying chicken.
I had the transmission rebuilt. I had the flex plate already and the mechanic installed it for no charge.
If your transmission has been removed the flex plate is attached to the back of the crankshaft by only 6 bolts.
Removal and replacement of the transmission is 98% of the work. The actual flex plate work is 6 bolts to remove and re-torque.

Petrol & Powder
10-23-2019, 06:46 AM
If the transmission is fine, don't rebuild it.

Rebuilding a functioning automatic transmission is like getting a root canal you don't need.

Removing and replacing the transmission is 98% of the work involved in replacing a flex plate but opening up a good automatic transmission is just asking for trouble and will about triple the cost of the job.