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98 Mustang Transmission Problems

04-07-2010, 11:22 AM
I am having problems with the transmission on my 98 Mustang. Starting on Sunday the transmission started slipping in 1st gear occasionally and I heard this loud screeching noise when accelerating in 1st gear as well. When it kicks into 2nd gear, the noise goes away. This got worse and it has been slipping really bad and more often. I had the filter replaced and had the transmission fluid drained and new fluid put in with a bottle of Lucas. It seemed a little better afterwards but it's gotten back to how it was again, slipping/jerking really bad in 1st gear and the noise is still there. It also started slipping in 4th gear really badly as well. Last night it slipped when shifting to 4th gear and the O/D off light started flashing. Today the light was off again and it is still doing the same thing.

I remember about a month ago it slipped/jerked really bad once when shifting to 4th gear but other than that I hadn't had problems with it. Now here's the thing. This car has 65k miles on it and it has already had the transmission rebuilt by the previous owner(well, they had a shop rebuild it). If a warranty came with it they don't have it anymore and it'd probably not be valid anymore anyway, because it's been a couple years I think. I'm wondering, am I going to want to get this rebuilt again or am I just going to have to get a brand new transmission put in since it was already rebuilt and there is problems again. Whatever is the cheapest route would be best for me but I don't want the tranny to mess up again any time soon. Also, when the guy changed the transmission fluid/filter, etc. there were a lot of metal chips/shavings in the pan and he said they were really big compared to what is normal.

04-07-2010, 11:34 AM
Just an update, I looked up info about a bad torque converter and this sounds EXACTLY like what I am experiencing. One of the things said it might cause reduced acceleration/lack of power and this is one of the things I've noticed.

HiFlow5 0
04-07-2010, 12:12 PM
I was just going to reference the torque converter as well as a potential problem area. For some reason it sounds like the vains are not filling with fluid while the converter is spinning. Could be from a failing front pump not able to supply enough line pressure to fill the converter. I've heard trannys with bad front pumps and they can whine like crazy as well. I would bring the car to a quality shop and have them look it over, also to verify that bands are not slipping either.

04-07-2010, 02:45 PM
Get a junkyard 4R70W. you can usually pick them up for under $100 and you can pick them from other vehicles besides the Mustang (i.e. Crown Vic, Grand Marquis, F-150). As long as it is a 4R70W, it will work although you may have to change the bell housing with the one on your current transmission and you may want to swap the accumulator springs so it shifts the same as your current transmission (or better yet do the J-mod). If there's any debris, be sure to flush the lines and replace the transmission oil cooler or you will just ruin whatever transmission you put in.

But before jumping on that band wagon, you did check fluid level, right? If it's low, there will not be enough fluid to fill the converter, engage the actuators, and lubricate the gears/clutch packs.

04-07-2010, 02:53 PM
I don't even know what a 4R70W is, lol. Well, I realize it's a transmission but yeah, I do not know anything about cars at all. I don't even know how to change my oil, though I'm sure I could figure it out if I wanted to. So even if I did get one I would have to find someone to put it in, cause I wouldn't even know where to start nor do I have any of the tools required.

As for the fluid level, I had someone flush the fluid and put in new fluid/Lucas and it is full now. One thing they did say was that the fluid that was in there before was really thin, like water. I'm not sure if that's relevant at all. But yeah, after that, it didn't seem to help it any; it's still doing the same thing.

I'm thinking I'm probably going to have to take it to a shop to have it looked at, I'm just not sure where to go. I don't know which places are honest, etc. around here. I'll do some googling though and find something out and take it somewhere when I get a chance.

04-07-2010, 03:44 PM
If you know anyone with some technical know how, see if they can help identify what year Ford cars have the transmission that will work for you. Like I said, I've seen perfectly good transmission had for $75-100, just had to haul it home (or in your case to a place who can install it). There's probably tons of these laying around with low miles after the Cash 4 Clunkers program. All those big Ford vehicles getting their engines destroyed with perfectly good drivetrains.

Oh and whether you get a new, rebuilt, or junkyard tranny, you WILL have to replace the transmission cooler as there will be metal debris in it which will destroy anything you install.

HiFlow5 0
04-07-2010, 09:22 PM
I'm not sure if a tranny swap is going to be something he will want to take on with basic automotive knowledge by himself, especially since he said he is not too familiar with the area, even if its only a couple hundred bucks. I've done a few tranny swaps by myself and its not too fun, especially heavy AOD's and such related autos.

To me is still seems like an issue related to the front pump, and if thats the case a full rebuild is in order to ensure longevity of the transmission. The previous owner may have had it rebuilt, but a poor rebuild can dramatically shortly the life of a tranny. If you are really stretched for cash, you may be able to find a tranny in a junkyard for cheap (no guarantee that it's not going to fail) and have a shop install it for you. I would still have it looked at by a shop, transmissions can be big headaches or minor inconveniences, have it diagnosed and then make your decision base on funds.

04-07-2010, 11:05 PM
Oh, I agree to take it to a shop if you don't have the tools/skills. I wouldn't tackle that without a good lift and some help. Those things are heavy. I also agree it depends on funding and how much peace of mind you want. Junkyard trannies are cheap but no guarantee how long they can last. They may last 10 more miles, or 100,000 more miles. A quality rebuild of your current tranny or purchasing a performance tranny may be well worth it.

Darrin at BCAutomotive is fantastic when it comes to rebuilt and performance 4R70W applications. A few customers I know paid the same price for these built up transmissions as they would have for a rebuild of their current transmissions with lower quality parts.

Don't let the site fool you, he's a very good guy and knows what he is doing. your local shop can install a shipped transmission just the same as any other.

04-08-2010, 11:27 AM
I might know someone that would be able to replace the transmission for relatively cheap if I can find one somewhere. There is a pull-a-part right by me and they have tons of the cars that are listed that have the 4R70W. I'm thinking about getting some estimates on a rebuild though because it might be worth it in the long run as some people were saying. From what I understand though, I have a bad torque converter. From researching it I have all of the symptoms of it and it seems like that will need to be replaced as well. I read that it costs a good $500-600 to get one of these replaced. Is this going to be on top of the transmission rebuild? Would it be any cheaper since they are already pulling the tranny out? I'm just looking for some ideas and trying to get a general grasp on this before I go out and get some estimates. Thanks

04-08-2010, 12:23 PM
Depends on the torque converter you get. A junkyard tranny may or may not have the torque converter with it. If the transmission is still on the junkyard car, chances are the TC is still in it and can be used again. Thoroughly inspect and clean everything, though.

Also, you can not just replace your TC. Since there's debris like you had mentioned, the entire transmission is compromised. Pull a transmission cooler, too, since that will have to be replaced. New coolers are cheap enough you can just buy new though. It's mounted between the radiator and AC condenser.

You can try that Pull-A-Part right by 480, but how it works there is you will have to bring the tools to remove it from a car yourself. That's why it's good to go there with a few friends to help remove it and inspect it. A good transmission place that my friend used and recommended to me when I was looking for some transmission parts for my J-mod is here:

It's in North Royalton, but shouldn't be more than a 30 minute drive for you.

04-08-2010, 01:47 PM
I took it up to this Aamco by me cause they had good reviews and I talked to the guy and he said 1400 - 1800 for a rebuild with a warranty. I asked about the torque converter too and he said that would be included. But he said they would have to look at it to give me an exact quote and that I would have to leave it with them, but I couldn't today. I'm going to have to drop it off some other time, tho I don't even have the money right now anyway to get it done.

04-08-2010, 04:18 PM
I forgot about the Aamco there. They are good from what I've heard, but never been to them myself.

That's probably the price range you'll see for a rebuild anywhere you go. I'd still see if you can't find a junkyard one until you do get the cash for a full rebuild. Ask them what an installation of junkyard transmission will cost, regardless of how long it may last you.

04-08-2010, 04:36 PM
Yeah, I imagine it will be around that price range for anywhere. I called that Buckeye Transmission place that you recommended and they said probably around 1200 to 1400. It probably won't take me too long to get the money together for it and I might have something else I can drive in the meantime. So I think I will probably just skip that step and save a little money and just wait and get it rebuilt. They said they have a 1 yr / 12,000 mile warranty at the Buckeye place. Thanks for the helpful information Blue and everyone else, I will keep you guys updated on this.

04-08-2010, 10:29 PM
Glad I could help. I would have offered to stop over and take a gander at it but I am out of town at college for the time being. Let us know how it goes!

HiFlow5 0
04-09-2010, 12:36 PM
I personally have not had good experience with Aamco, they did a rebuild for one of my cars many years ago and botched the job bad. Pinched the seals, tranny had a hang up condition and performance of the transmission was very poor. I spent close to the same price you mentioned above as well.

I then spent $300 on a used transmission and stall converter combo with about 3k miles on it that was far better build then the Aamco build. That tranny lasted me the rest of the time I owned that car and many many trips to the track as well.

If you really found someone that could do the swap for relatively cheap money, then it might be a alternate option then spending close to $2000 on a rebuild. The place Blue recommended might be a much better option then AAmco too.

04-09-2010, 01:37 PM
I think I've decided I'm going to take it to this place called Atlas Transmission down the street from me. I've heard good things about them from quite a few people and they quoted me 1200 bucks which isn't too bad. I forgot to ask about the warranty but I'm sure it comes with a warranty as well, I will ask about that. I'm not too worried about the cost, I'll be getting help paying for it from the person I bought it from(my brother). I'd rather have something reliable even if it is gonna be a little(a lot lol) more. I have a guy that does work on my car for pretty cheap but I'm not sure how well versed he is on transmissions. I'm sure he could probably pull it off, but yeah. It's not a big deal, just gonna get it rebuilt.

HiFlow5 0
04-09-2010, 02:38 PM
Sounds like a wise choice, good luck.

05-05-2010, 10:20 AM
Hey guys. I dropped my car off the other day and got it back today. Basically I was told that the transmission was completely destroyed and there was no way to rebuild it. They replaced it with a rebuilt 4r70w that they had in stock instead. Now the check engine light is on and it was never on before. I am wondering if this is because of everything being taken apart and if this will go away in some time or if they messed something up. Also it still feels like it's kind of difficult to accelerate, is that possibly because the transmission needs to be 'broken in' or is it possible that it wasn't because of the torque converter and it's something else? Torque converter was replaced too. Btw I know pretty much nothing about cars. But thanks!

05-05-2010, 01:39 PM
The CEL should not be on. There is no break in period. Get the codes read and post the exact codes here.

05-05-2010, 02:49 PM
I talked to him and he said for me to bring it up tomorrow and he will look at it. I assume they will have to fix anything at no cost if they messed anything up because the CEL was never on before.

05-05-2010, 11:11 PM
It really depends on the code. It may be completely unrelated and just coincidence. But if it's something that could be related, you should try your best to make them flip the bill.

Also, this is a good reason to get your codes read somewhere else first. That way you know exactly what the CEL is on for so they can't tell you something different.

05-06-2010, 12:40 AM
I really doubt it is unrelated. It is possible, however would have to be a MAJOR coincidence since it has never been on before, and was on immediately after getting it back. I think I will consider taking it to somewhere else first to have the codes pulled, thanks!

05-06-2010, 09:52 AM
Go to any Autozone or Advance Auto. they will get the codes for free. Take a pen and paper and right down the codes to post here, not just the description they give you, since they are usually not accurate enough.

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