5R55E Transmission jerking repeatedly

[CAW]

Over the past week my truck has been having an issue which I can only assume is transmission related. When I drive at 50-60mph the truck will jerk several times, as if it is trying to shift gears and can't decide which gear to shift into. This only happens when shifting to a higher gear and not when slowing down from the problem speed range. The symptoms have been happening more often the last week. Sometimes the symptoms go away, or at least get better when the truck has been running for 5 or 10 minutes.

I am a bit of a novice when it comes to transmission work. I have checked the fluid level and it was full. The fluid and filter were changed about a year ago. The transmission code on my door sticker is "D" so I believe I have the 5R55E. I have heard that these can have problems with the valve body gasket blowing out? Another possible cause that I can think of would be a solenoid going bad. Perhaps the coil is effected by the vehicle warming up, making the problem intermittent. It always helps to get someone else's opinion. I would be totally open to any advice that you guys could give. Thanks!

1997 Ranger 4.0 OHV 200k miles 4x4

 

[RonD]

A transmission shop can usually read any codes the computer might have set for transmission problem, generic OBD2 scanners can sometimes get all the codes but not always.

Yes could be pressure issue, gaskets, seals and valves, or solenoid not holding.
Automatics run/work on pressure

And yes it would get worse as ATF heats up and gets thinner, like all oil does.

Really is a guessing game, trans shop can do line pressure checks to see if pressure is changing when it shouldn't, but still hard to narrow it down to "this is it".
You can OHM test solenoids, cold and then warmed up, but it often won't be definitive until solenoid fails out right.

Additives like Lucas AFT can help soften and swell gaskets and seals, slowing leaks, doesn't "fix" anything though.

 

[CAW]

It seems that the problem has become slightly more noticeable. And I have made a few more observations. The transmission shaking repeatedly only happens in 4th and 5th gear. I used the OD cancel button to keep from shifting into 5th and the problem was still present but not quite as violent as when in 5th. I got a shop manual with a table that lists what solenoids and clutches are active in a particular gear. However, I couldn't find any components that would be common between 4th and 5th gear. The repeated shaking happens to be the worst when the accelerator is applied. Under slight throttle the problem stops as long as the vehicle has been driven for several minutes to get wormed up. It is very strange that the problem actually gets better as the transmission warms up. It is not throwing any codes either. I am getting worried that I am going to burn up a clutch in the transmission. I may end up removing the valve body to check the gaskets and investigate further.

 

[Transman304]

Sounds like a torque converter lock up issue. But with no codes I may suspect an ignition issue. Your O/D light is not blinking on the shifter knob? A quick check for VB gasket issues is to see if the truck holds back in low gear. If it does not your gaskets are likely bad. This check works about 90% of the time. Good luck and keep us posted. You can also ck the lock up by just laying your foot on the brake pedal and start to apply pressure while it is jerking and this will cancel lock up and see if the jerking stops.

 

[CAW]

A few days have passed and the issue seems to be getting more frequent. Today I was driving home and it was shaking/jerking worse than it had been. The CEL came on and was blinking. I pulled over, turned off the engine and opened the hood. Nothing was obviously wrong. I waited a few minutes then cautiously started the engine. The CEL was still on but no longer blinking. I drove home, got out the code reader and found P0305 Cyl #5 Misfire. I thought for sure that it was a transmission issue. It felt just like it was trying to change gears and only happens at 45+ MPH.

The pieces of the puzzle may be coming together. My truck has other issues that I thought were unrelated.

If I let the engine warm up, then shut it off and wait for 15-20 minutes, then start it, It idles very rough for a minute or so. I made a thread about this a while back. Someone suggested I press the gas pedal to the floor to use the auto choke feature to turn off the fuel injectors while cranking the engine to see if an injector was leaking. I tried it and all seemed normal.

Cylinder #5 is the middle on the drivers side, I believe? I have had to replace that valve cover gasket twice. The latest time was a year or so ago.

On occasion, I have heard a ticking noise. It is consistent with vehicle rpm. In the past I had blamed this on either an undiagnosed bad bearing or my all-terrain tires which like to pick up rocks and make a ticking noise as I drive.

Now I am wondering if this could be a valve train issue? I need to check the coil pack and spark plugs and simple stuff before jumping to any conclusions.

 

[CAW]

It ended up being a bad coil pack. I had checked Cylinder #5 with a spark tester and it lit up as the cylinder fired. I had previously discounted the coil pack from being bad for this reason. Upon closer inspection, the coil that ignites #5 and the opposite cylinder measured a much higher resistance than the other two coils on the pack. The intermittent jerk felt more violent than a cylinder simply not firing. I am wondering if #5 was somehow being ignited at the wrong time by another coil. But none the less and to my surprise, changing the coil pack fixed it.

Thanks for the replies!

 

[Transman304]

Glad it worked out for you. Great detective work! Thanks for the update.

 

[RonD]

Yes, good find.

Thanks for posting the fix