Not so Good Vibrations

[whtbronco]

Based on the chart below I bet my scanner is reading the EPC solenoid pressure and not actual line pressure. I just can't believe that if my trans pump was around 20% of the low side pressure that it could even grab a gear. The EPC pressures I saw are on the low side of this chart, but within the ranges, that makes more sense since I have no shifting issues.

 

[kep5niner]

Helluva quest to get this figured out! I can see how a shop would’ve tossed their hands in the air a while ago, and just tried to sell you a new $100k Expy instead of figuring out the problem.

Nice work! Stay at it!

 

[whtbronco]

Thanks kep5niner.

LOL, yeah and even a very reasonable shop would have probably cost me a fortune at this point. Course a lot of true mechanics would be better at troubleshooting than I am, and a lift would help tremendously. $100k for a light duty truck of any kind is just crazy to me. Maybe all my rambling will help someone else someday. It's already allowed me to go back and read what I did so I guess that's good.

We've driven 11 trips in the past 2 days and about 200 miles with no misfires so what caused that the other day is beyond me. We have had that occasionally though over the last 20yrs. It'll just misfire for 30-60 seconds at or shortly after startup, every now and then. Since I never found a cause I just chalk it up to computer/sensor issues. My wife commented today that the vibration felt the worst to her at 1000rpm and decreased as she went faster, and that it's very smooth at full throttle now following the transfer case swap.

 

[whtbronco]

I wasn't able to touch the truck over the weekend. This evening I decided to just check the engine accessories again since I didn't have very long. I popped the belt off, it's certainly smoother without the belt on it and low and behold my water pump is weeping a bit. I found a bit of coolant on the bottom of the steering rack. So that will get changed this weekend, got a Motorcraft pump on it's way. I also think the A/C compressor doesn't sound real good, not terrible though. However, correct if I'm wrong, but I don't think either of those would cause the vibration to get worse while coasting/decelerating. So there may be yet another issue. I'll do the water pump first and go from there.

 

[whtbronco]

The water pump has been replaced. I took the opportunity to flush the coolant out, it was on my list to do so now was the time. With the pump and thermostat out and then pulling the heater core hose from the intake it's pretty easy to get most of the coolant out of the block as well.

I really wish the 5.4 had an air bleed screw.

Certainly running a bit smoother, I just did a short test drive though so I'll know better after I go to work Monday.

After dealing with the removal of the fan again I am seriously thinking of putting in electric fans. It's is so freakin' hard to loosen the fan clutch from the water pump by myself. Even with a dedicated fan clutch tool set, it's a PITA. In fact I don't even try to use that clutch wrench, just the pulley wrench.

 

[kep5niner]

After dealing with the removal of the fan again I am seriously thinking of putting in electric fans.

DO IT! Throw the Volant air intake on there while you’re at it. They do include a 15% military discount as well - it’s like they’re paying you at that point.

PM me if you’ve got any questions. You won’t regret it!

 

[whtbronco]

I'll keep the fans and intake on my list. That list got a good bit longer recently. One of the list additions is a trans pan gasket on my sons Ranger. It's dripping on the cat so that is right at the top of the list and will replaced tomorrow night. Next up for the Expedition is to cut out the rust in the trans cooler lines from the clip that holds them together at the bottom of the radiator. This was identified during the water pump replacement and appears to be fairly common, just as common is not being able to find the line that runs cooler to radiator. So I'll cut, flare and clamp in some trans hose.

The water pump replacement resulted in 2 things. It showed that I had both a high and low frequency vibration, I figured this might be the case. It resolved the high frequency vibration.

The low frequency vibration remains and is low rpm, certainly not engine rpm. What makes no sense is that it doesn't seem to get faster as speed increases it just becomes more pronounced. It begins at 32-33mph and continues to 80mph, haven't tried faster but it would be there. It's just barely noticeable under cruise power or heavy load, moderate under light power load and very pronounced when coasting. Dropping it into neutral doesn't help much. It's primarily noticeable in the seat and floor, course if I get on the brakes I can feel it in the pedal and the steering wheel. What's interesting and it might be just a mental issue, is that it seems I can feel it under braking down to ~25mph coasting it goes away when I get down to ~33mph. 25mph or below it's not noticeable and very smooth now. It does seem to be worse after 20 miles or so on the interstate, so heat is likely playing a part.

The salvage yard transfer case is now leaking at both output seals despite having new bearings and seals throughout. I can't help but wonder if the transfer case is the cause, it wasn't well cared for by the previous owner. So that's next on the vibration hunt since it's getting done anyway. I am going to put new bearings and seals in my original transfer case, hopefully this weekend. Then next weekend I'll swap them and we'll know.

 

[whtbronco]

The Ranger trans pan gasket has been replaced, the trans cooler hoses were leaking so they were replaced and I ordered an entire gasket kit for the engine. My goodness I was shocked, the valve covers and/or intake are leaking oil and it's covered both side of the block, the oil pan is leaking, the rear main seal has been leaking for a while. Thinking we'll pull the engine out to replace the seals, ugh.

The original transfer case for my Expedition now has new bearings and seals. What a difference between mine and the salvage yard unit. Mine was clean inside with nice red fluid, which I knew, the clutches look really good in comparison and had no pealing of the anodizing, and far less wear despite having 60K more miles on it. I don't think the fluid was changed much if ever in the salvage yard unit, so maintenance makes a difference. After I reassembled the salvage yard transfer case I thought it felt good, but the original one is so much better. Smoother, quieter, easier to turn. This bearing and seal kit had different bearings and that may be part of it. The other thing that surprised me is how easily the case went back together this time. I fought with the salvage yard unit to get it back together, this one just fell together quick and easy. Picks below for comparison.

I don't think the remaining vibration is the transfer case, but next weekend I'll swap the original back in and find out. With any luck I'll also get to repair the rusted trans cooler lines. The plan is to cut out the rusted part of the lines, bubble flare the ends and slip some hose on.

 

[whtbronco]

Not sure what I was thinking the other day when I noted that the vibration was present to 80mph, maybe it should have been 70mph. Anyway, today I pushed full throttle from 0-70mph and couldn't feel it at all until I backed off. It's present from 32-74mph, really starts to go away about 70mph. I think it just gets so fast I can't really feel it anymore. It means it's wheel speed related for sure though. Yesterday I had a 2 brief periods of no vibration at all which caught me off guard and I can't explain it.

I have basically decided that if the transfer case doesn't resolve it that I'm back to the beginning. Putting up on jack stands, checking suspension and running it up to speed while I climb around underneath listening and feeling.

 

[whtbronco]

The transfer case has been swapped again. I have not yet been for a test drive, probably be tomorrow.

Before the swap I spent some time looking for things are loose or had play in them. I found 1 thing, the support bracket for rear diff, aka torque arm. There's no real play from neutral to reverse, but neutral to drive there's like 1/8-3/16" so that's gotta be replaced. That said the factory part is not available and I have not found a new one on eBAY, Amazon or such. Below is what I found regarding a replacement. I think this will work so I'll probably take my chances on the 8L1Z part and hope it works out.

I'd try just a replacement bushing. I haven't yet found that either, but I'm still looking.

Torque arm assembly:
4L1Z-4612-AA (03-06 Expedition) all 4yrs of the Gen 2
5L1Z-4612-AA (05-06 Expedition) really just 2yrs of the Gen 2
8L1Z-4612-A replaces 5L1Z-4612-AA and 7L1Z-4612-A (07-17 Expedition) some places show this fits 05-17 Expeditions so why would this not fit the 03-04.