Hostgator

The codes you indicated actually have nothing to do with the problem your Xterra is experiencing. The problem is with the electronic feed to the dash panel’s combination meter. This electronic device handles the varied outputs you see when you turn the ignition switch. Believe it or not, though there are many circuits involved, there is one control module that runs the whole thing. It is a 40-pin header that includes, among other things, the displays for your fuel, coolant temperature, automatic transmission status and the like.

While the problem you are experiencing may seem transmission-related, it is more correctly an electronic problem with the display control module. From looking over the schematics, it looks to be line 20 of the 40-pin device that controls the fate of your transmission status display.

You will need some specialized test equipment to check out any problem with this module. At the very least, you will need a good volt-ohmmeter to test the voltage levels that are required, if you feel you are qualified to handle the chore. It is rather tedious, to be honest, and requires constantly checking to see the exact voltage values. They are also easy to miss.

You will need someone expert in working with this type of equipment to handle everything. The good news is that it is unlikely to keep you grounded because, as far as I can determine, there is no linkage between that module and the other key modules of the automatic transmission circuit.

At least you know one good thing, the transmission isn’t at fault here. The fact is I don’t think it is even contributing to your Toyota’s problem. Look elsewhere for the problem. I suspect you may have a problem with the cooling system as engines seldom shut down in the manner you describe unless there is something catastrophic about to take place, like a meltdown or something.

Be sure to check the coolant level in the plastic reservoir to make sure there’s enough anti-freeze/coolant in the block so that your engine won’t turn into a pile of molten metal.

This sounds like a problem with the shifter itself. There are any number of reasons that this might be happening. Here’s a list of the possibilities:

— A shifter problem: It’s possible that the shift mechanism could be wearing out and needs to be replaced. It might keep your transmission stuck in Park and not shifting at all. You may need to have the shifter mechanism replaced.

— A shifter lock problem: When you slam the shift into Park, you not only set the pawl that locks the output shaft and keeps the transmission from spinning, but you also effectively lock the shifter as a special lock engages. The lock usually releases when you press the brake after you start, but sometimes it doesn’t. It’s a fairly easy fix that involves popping the tab of the shift lock override unit and pressing the button beneath, while your foot’s on the brake. Your shift will slide out of park and you will be able to start but you will have to get to a service area before you can engage Park again. The override unit is the tiny button-like access panel you will find on the gearshift console near the unit.

— A neutral-start problem: The switch might be wearing out. This switch, which works with the shift interlock solenoid, requires you to press the brake before you can release the shifter. This could be sticky or the solenoid could be failing. Also, there might be a wiring problem.

— A shift interlock solenoid problem: The shift interlock solenoid which requires you to press the brake before you can engage the shifter may be failing. It might be a wiring problem or a problem with the solenoid itself. It’s something that you should have your mechanic check.

— A gearshift cable problem: The gearshift cable may be stretched and may, at times, bind, preventing the necessary take-up so that you can shift out of Park.

As you can see, there are a bunch of possible problems that may be affecting your SUV. For my money, I would check the gearshift cable and the interlock solenoid. Either one can cause the problem you describe — as can the others but not so intermittently — and can keep your transmission locked up.

Here’s a good new-bad news answer. The good news is that your Frontier’s transmission is still working nicely at 150,000 miles. The bad news is that there’s no way to get to the tail bearing you mentioned without getting into the transmission in a major way.

You can breath a little more easily, though, when you realize that even though they may have replaced the major components of the transmission, there are still other parts that have remained the same. And, due to uneven wear rates (newer versus older), it’s honestly quite right to expect a bit of oddity now and then.

To be truthful, either you live with the strangeness, or you are going to have to shell out another, say, $1,500 to have the problem fixed. The reason it won’t be $2,000 again is that you have already replaced most of the MAJOR parts, but there are still one or two that likely need replacement now. Once you have had that service performed then your transmission and your Frontier will be happy campers again.

It’s quite possible it could be a lazy solenoid, though, when they fail, they go down hard and stay there. With that said, though, you might still be in luck. You see most transmissions are controlled by the transmission control module (a fancy way of saying a specialized computer). The control module looks at many inputs including a number of sensors such as the mass airflow sensor, the mass air pressure sensor, the throttle positioning sensor and even a thermostatic sensor that ensures the transmission is operating within performance specs.

It is quite possible that one of those sensors could be failing and that could be causing your problem. It’s easy to check out as all you have to do is ask the technician to run a diagnostic scan with an OBD-II scanner and if there is a problem code stashed away, it will show up. It will tell you the part or area of the transmission that is failing.

Now, here’s a suggestion that is always a good starting point. Take a look at the transmission fluid. One part of my mind keeps on being nagged by the jerking as it goes into fourth. It could be a slipping clutch/band combination or it may just be that your transmission is slightly low on fluid. When this happens, the transmission relies on increasing internal pressure to compensate for the lowered fluid.

It’s one of those things that works most of the time and sometimes slips. It sounds like your transmission could be low just enough fluid so that all of the parts of fourth gear are mostly covered and work correctly, but there are times, say when accelerating, when there’s just enough force holding up the transmission fluid flow to make it go clunk. And, while you are at it switch out the transmission filter as it might just be clogged enough to prevent adequate fluid flow at times.

You can’t really see anything yourself as you have to have a trained technician with an OBD-II diagnostic scanner plug in and take a look. The chances are good there’s an error code stored with 07 as the first two digits. That indicates it is transmission-related in most cars. From there on out there are two other numbers which narrow things down. However, you don’t have to know what the last two numbers mean as the scanner will give you the entire error code.

Your technician can then look at the error code and see where the problem is.

With that said, at this point, I would advise you to have the transmission replaced with a rebuilt transmission. A rebuilt transmission, by the way, is only “rebuilt” in name only. When it arrives at the shop, it’s really a new unit inside a used housing. It is less expensive for you this way. It will cost you between $3,200 and $3,400 but when it’s done, you won’t be having the problems you are having now.

Can I ask you for a bit of help? You say: “…he advised me to change [the] complete gear box…”, right? No, I am wondering, do you mean the transmission or just the gearbox? And, if you are saying gearbox, does your Toyota have a stick? Most of the time, when I see an all-wheel-drive or 4WD vehicle, it usually has a four- or six-cylinder engine that’s hooked up to an automatic. Is this the case? Please send me a short note with an answer and then I’ll be more in a position to help.

While you are sending the note, can you also let me know if you have lost any gears and whether the CEL (check engine light) has flashed on? If either condition exists, it means you have significant problems. Please let me know, asap.

Your Dakota pickup is likely suffering from a case of bad synchronizers. Since the 1960s, manual transmissions on smaller vehicles have had what is known as synchronizers installed on each gear. The purpose of the syncros is simple, it keeps the gears from clashing together when you shift from gear to gear. (Standard transmissions, unlike automatics, make you do the work of shifting. As you go through the shift pattern, each gear will link and then unlink as you move up toward overdrive. Until the 1960s, you had to match the speed of the gear you had selected and were shifting with the speed of the already-spinning gear choice in the transmission. If you didn’t match them carefully, the gears clashed and ground, possibly causing damage. Enter the synchronizers which handled matching the speeds automatically so your gearshifts were smooth and seamless.)

I suspect the synchros on first and second in your Dakota are shot and should be replaced. The reason I am suggesting this is simply that they work for the first few minutes and then stop. This is one sign that a part has failed or is on the way to failing but hasn’t quite made it yet.

I would get the problem seen to quickly as it is only a matter of time before third, fourth and fifth joint first and second. If you have it repaired now, it will cost you about $700. If you wait and the repairs become more extensive, you are looking at easily doubling that expense.

It looks to me like both of your solenoids failed at the same time. There are two, you know. If you only replace one (there’s one that’s pretty easy to locate on the valve body and the second which is inside the valve body and isn’t easy to reach) and if the second has gone, your vehicle will hang up in gear and not shift.

You will have to take Explorer to a specialist to see where the problem lies, but, I honestly think it is in the electronics.

If only one of the two solenoids has gone, then it is possible that a sensor or sensor cluster has passed out and isn’t working any more. This may have caused a cascade effect on the electronic side of things, taking out several systems.

Here are the steps to take to see where the problem is, since you know it’s likely an electronic fault (your Explorer is in limp-home mode, by the way, among other things):

1. Get to your service area
2. Have your technician put an OBD-II diagnostic scanner into the diagnostic slot at the left-hand
side of the dash panel
3. Read the codes
4. Pinpoint where the problem is

I think it is very likely that this will reveal exactly where the problem is because I think it is strictly electronic.

Having gone over the 12 or so possible causes of your Camry’s problem and having re-read your description, I have to think that the problem is with the torque converter. In order for the Camry to suddenly stop moving in traffic, it has to be that particular device. You see, when the torque converter goes it is a sudden failure, just as you described.

The torque converter is the first step in your transmission’s actions. Taking the power from the input shaft before it splits off to power other devices, as well, the torque converter spins up and starts moving the transmission fluid throughout the case. Without it working, setting up the current, so to speak, your transmission doesn’t work.

Now, it is entirely possible that your transmission filter could be plugged up, preventing the flow of transmission fluid. There’s really no way to see if this is the case, other than draining the fluid, dropping the tranny cover, making sure there’s a bucket underneath to catch any drips, and locating the filter to check it. You can do this work to save a few dollars as it is straightforward and only involves a wrench (10 mil or so), the bucket, new gasketing to seat the pan correctly when you sock it up and the proper amount of transmission fluid.

With that said, I honestly think your primary candidate is the torque converter, in this case. If it is the torque converter, your best bet is to insert a rebuilt transmission (transaxle, really) in place of the old one because it is a major repair and a new converter, if that is the only device swapped out, could start putting higher pressure levels on other components that may be marginal, pushing them over the edge. The rebuilt transmission will cost about $3,400.

Here are a couple of thoughts. First, I don’t think your van’s problem is transmission-related. You said it yourself, when you hit the overdrive button, your van run smoother. It is entirely possible that your transmission’s clutches are slipping, which also means your bands aren’t doing their job, either. However, they aren’t all that far gone because the are, at least, working correctly part or most of the time. It is also possible that your transmission could be slightly down on transmission fluid. If that’s so, then your van would definitely perform the way you describe.

Honestly, I think your problems are mechanical. You said you are a carpet-installer and that means you are constantly carrying room-sized rolls of rolled-up carpeting. From what I have seen when the carpet guy sets up one of the units where we live for a new occupant, your truck is like-as-not loaded to or over capacity. If that’s the case, they your van’s engine would be straining and could easily perform poorly, skipping or misfiring. This is happening because the load you are carrying in the van is too great for the vehicle’s gross vehicle weight rating.

I can easily understand how this can happen as you do have to cram every bit of carpeting for a job, your tools and then yourself, and, possibly your crew, in the van. Instantly, you are over-rating and poor performance ensues.

Here’s a suggestion, if you have the time. After your next big job, when your van’s cleaned out pretty well, find the steepest and tallest hill in your city and then begin a steady-state trial run up the hill. A steady-state run is keeping your foot on the accelerator and watching that the speedo doesn’t exceed, say, 25 mph all the way up. If the hill is steep enough and tall enough, you should find at some point your van’s performance is impaired. It should begin to perform in the manner that you describe. If it doesn’t, then I will admit that it’s likely a transmission problem that is linked to slipping clutches and bands. It will cost between $1,800 and $2,400 to have a clutch/band issue diagnost and repaired.

Your car is going into limp-home mode very quickly because there’s something very wrong with its transmission. Normally, when a car goes into limp-home mode it has experienced some event where the transmission control module (TCM, the computer that controls your transmission and works with the engine control (ECC) module) takes various inputs from the sensors it monitors (mass air flow, mass air pressure, speed tensor, throttle positioning sensor and such) as well as from the sensors the ECC monitors that work with the transmission decides there’s a problem and puts your transmission into a state where it will limp along in a forward gear or in rear and a forward gear, giving you the ability to get to a service area or to your home where you can have the vehicle towed in.

What happens is that a computer code is sent to the ECC or TCM that says the “XYZ is bad, go into limp-home.” Then, your vehicle performs very much as you indicate. It can be more than just a simple code, though. In fact — I think this is the case with your car — it may be that a mechanical part has plainly gone and the resulting performance is because of the bad system.

In your vehicle, I think it is a combination of systems, so many systems that you can pretty much think rebuilt computer and $3,000 to $3,800 expense from the start. As to the specific systems that may be involved, it sounds like there could be a problem with the torque converter and the input turbine impellers that, combined with a problem with the clutches/bands and gears, is rendering your car undrivable.

I could sugar-coat it and tell you to have this system checked and then that system checked to keep your costs down, but, when you add up all of the potential diagnostic work that might be involved, you are looking at a lot more than the $3,400 average figure. The cost is greater because you have to add in the various checks to the cost of the replacement transmission you will be having installed.