Disconnect Torque Converter? - Transmission Slip between 1st and 2nd

[LeonJack]

Hi,

I own a 1999 Ford Explorer Sport - 4wd 4L SOHC - Automatic Transmission

At 25mph / 3000 rpm, when Explorer attempts to shift, the engine revs and the rpms will jump to 4500 / 5000 rpm, until I let off the gas, then it will shift into 2nd gear (or 3rd?).

However, if I accelerate very slowly, the engine will rev slightly at 25mph (3500 rpms) but eventually shift on its own (without me letting off the gas).

Also, this is the only gear that has the problems, shifting between all other gears works great!!

The Ford Service center says that the transmission is not holding the pressure to shift properly at this gear. They suggest replacing the transmission. (But this is expensive).

I tried adding the Lucas Transmission treatment, but it is still doing the same thing.


I have two questions for anyone that would be kind enough to offer some advice:

Does anyone know of a sensor that might cause this kind of problem?

If I unhook the wires to the Torque Converter, will it fix this problem (even if it is temporarily)? And if so, how do I unhook the wires to the Torque Converter?

Thanks for the help.

 

[BrooklynBay]

Welcome to this forum! Your shift flares on the 5R55E might be a result of low hydraulic pressure from a failing EPC solenoid, bad VB gaskets, or loose VB bolts. How many miles do you have? I would suggest that you read Glacier991's 5R55E VB rebuild diary thread. It's a sticky on top of the transmission section.

 

[LeonJack]

Thank you.

I will read Glacier991's 5R55E VB rebuild diary thread.

The Explorer has 131,000 miles.

Someone told me that unhooking the wires to the Torque Converter is a "quick and dirty" solution. Is this at all reasonable?

 

[BrooklynBay]

The wiring is integrated into the harness, and is recommended not to disconnect. The EPC, and TCC solenoids are modulated. The other shift solenoids are basically switching on, and off. The modulated solenoids have a variable open, and close, and usually work by PWM. This means that they have a variable duty cycle. Duty cycle is the time on compared to the time off. 0% = off, and 100% = on.

 

[LeonJack]

Do you know of any "quick and dirty" solutions to make the transmission shift properly between 1st and 2nd (until I have the time and/or money to fix the transmission properly).

For example adding more Lucas transmission treatment?, etc?

 

[NHale623]

When's the last time you changed in the fluid in the transmission? How many miles are on it? Is your O/D Off light flashing?

There probably isn't a quick and dirty solution. I wouldn't add any more treatments to it.

 

[LeonJack]

I changed the transmission fluid and filter at 65,000 miles and right after I started having problems at 131,000. (Explorer currently has 131,000).

Yeah, seemed like a bad idea to add any more treatments to it.

The O/D light will start flashing if I don't let off the gas in time, (to allow it to shift), and the engine rpms get too high (between 1st and 2nd). When I turn the Explorer off, then back on, the O/D light is no longer flashing until I don't let off the gas in time.

Also, when the O/D light is flashing, I notice a huge difference in acceleration, (it accelerates much slower - almost feels like like a huge weight is being tugged). This goes away after I turn off the explorer and turn it back on.

Thanks for your help.

 

[NHale623]

I think you should get the codes read. Post them here, and someone can help you figure out your best course of action. But I gotta think that 131,000 miles is not too bad when you consider the 65,000 service interval. You should probably plan for the worst, and hope for the best.

In the meantime, driving any distance with the O/D Off light flashing is very hard on your transmission. You'd be very wise to avoid it as much as possible. You'll want to read this thread, especially the second post: http://www.explorerforum.com/forums/showthread.php?t=170235

I'm sorry I can't be more help to you. Good luck.

 

[LeonJack]

In all my worrying about the transmission I forgot to mention one thing. I don't think it is related but I'll give it a shot.

About 200 miles before the shifting problem the "Check Engine" came on, (and is still on today).

I brought the explorer to the "Advance Auto" and hooked up the reader. The code readouts are the common ones - P0171 and P0174 - system bank 1 and 2 running too lean. Exporer wass running fine, very quiet, very smooth - so I didn't think much of it at the time.

At 75,000 miles I had the Recall fixed for the leaking intake manifold gaskets. So, I'm pretty sure the codes aren't related to that again. I'm going to try to clean the MAF sensor with some electronic cleaner, check the air filter, etc. - Hopefully it is the reason for the P0171 and P0174.

I'll let you know if this for some strange reason helps the shifting problem - (I doubt it, but I'm hoping it might for some reason??).

 

[1karkrazyguy]

Hi LeonJack,

First off, if you don't have the money to fix your transmission problems and if you plan to drive the truck/transmission for awhile with a check engine light and especially a flashing OD light, plan on doing a complete rebuild of your transmission at some point in the near future. With your transmission problems, your Powertrain Control Module, (PCM) is telling the EPC solenoid(transmission electronic pressure control) to run at maximum pressure to try and PROTECT the internals of the transmission and to try and minimize the damage to it.

Second, please understand that the engine and the electronically controlled transmission are an integrated, computer controlled system, controlled by the Powertrain Control Module or PCM.

The PCM adjusts/controls the shift patterns in your transmission based on engine controls, ambient air temp, engine and transmission temps, driver style of driving and engine and transmission loads/conditions.

I would NOT recommend disconnecting the TSS and I would think the PCM would put your transmission AGAIN into a limp mode with EPC pressure at maximum to prevent damage.

At your stated mileage, you could/probably have a mechanical condition/problem in the transmission. Yes, transmission hard parts do wear out/break with age; for an example friction material wears on bands and on clutches, securing points break on bands, etc.

I agree with the posts here. Get the OBDII DTC codes for your transmission problem. Try to drive the truck as little as possible because of the flashing OD light as you will cause more damage to the transmission by driving it.

If you can not find a local ATRA member, take your truck to your FORD dealer and get all trouble codes read out and WRITTEN DOWN on your worksheet.

If a FORD dealer is a no go for you, take your truck to a transmission specialist in your area that is a certified ATRA, www.atra.com, member. Go to their website and find a local member.

Again, watch them as they work and have them WRITE DOWN the DTC codes from your vehicle. Then come back here and post them and we can try and get you some intelligent and helpful info for your problem.

Hope this helped. Good luck.

 

[LeonJack]

Thank you for all the replies.

I've cleaned the Mass Airflow Sensor and changed the Air Filter. The Check Engine light has not came back on. Transmission is acting the same.

I've brough the car to the Ford Dealer and Cottman Transmission. The Ford dealer has told me it will cost 3000 - 3500 for a transmission, he told me that considering how much the car is worth, he would seriously consider not fixing it - just move on :thumbdwn: . (Cottman Transmission same price).

Anyone know if it is possible that I would just need to replace the Torque Converter, and do I have to remove the tramission to get to the Torque Convertor, (is it easy to replace)?

Thanks for all the help.

 

[BrooklynBay]

I would suggest that you try a VB rebuild first. The torque converter might not be the problem. That would require dropping the entire transmission. If you would do that, then it would better to rebuild everything at the same time.

 

[Glacier991]

You DO have to remove the Tranny to replace the TC.... and yes it is a major PITA.

 

[Doubt Incarnate]

i second (3rd? 4th?) the VB rebuild. I got my ex about a year and a half ago. had like 124K on it and leaked tranny fluid. I swapped the pan gasket and the filter since i had to buy it to get the gasket and this event let a bunch of fluid out and something waiting to happen, happened. Needless to say i ended up with the traditional shifting flare and after rebuilding the vb as glacier991's diary walk you through it was good to go. cost me probly around 2-300 since i had to buy tools, but i saved like 500 over the local shops quote.

but i still leak, who ever designated the routing for the exhaust system needs to be shot.

 

[LeonJack]

Thanks again for all the replies. I've learned alot about doing my own repairs owning this explorer. It's been frustrating, and sort of fun too.

Now the transmission slipping problem was occuring before what I describe below, but....Just want to know what you think.....

One thing I noticed when installing the new transimission filter, (at 131,000 miles filter/fluid change) is the the transmission filter didn't fit snuggly at the rear hole.

More specifically; The filter / transmission has one big hole toward the front of the vehicle and a small hole toward the rear. The filter (gasket) fits snugly in the big, front hole, but loosely in the rear hole, (like the filter gasket doesn't quite seal - filter to transmission - on the small hole). Is this anything to worry about? Would this immediately affect transmission performance or merely not filter the transmission filter properly?

Either way, it seems I should get a new filter, (Not from Advance Auto this time - from Ford).

(Which reminds me - if you ever need new lug posts for your wheels - get them from the Ford dealer. I got them from a few different Auto Parts stores and they were so far off spec - amazingly bad they could sell those to people.)

 

[NHale623]

Did you put the o-rings on the filter before you installed it?

 

[LeonJack]

Yes, O-rings were were on the filter before install.

Weird it didn't fit snuggly.

 

[BrooklynBay]

What brand was the filter? Glacier991 once mentioned in another thread that the Ford filter is the same as the Fram micro felt. You might be losing suction on the sump from the loose fit, and could be pumping air along with ATF.

 

[LeonJack]

BrooklyBay,

I don't remember off the top of my head.

However I just called the Service department a different Ford Dealer in the area.

The technician said that this problem is often caused by a blown or damaged Valve Body Gasket. He said they are able to replace it without dropping the transmission. (Good news). He has quoted me $400 - $500 on the Valve Body Replacement, ($120 to drop the pan for diagnosis)

I will reread Glacier991's 5R55E VB to see how difficult it is to replace the gasket. If I don't have to drop the transmission - I should be able to do it myself.

 

[BrooklynBay]

You don't have to drop the transmission to replace the valve body. The gaskets are now bonded to the separator plates, so you buy them as a single unit. Check WWW.TransmissionPartsUSA.Com for them.