2003 Excursion 4wd. Noticed a few days ago that when selecting reverse, it seemed to take longer to actually go into gear. Didn't think much of it and it has been fine since. Pulled the camper a few hours away for the weekend..

Now the truck is slow to engage reverse. Even when warm, when I put it in Reverse, it takes up to 30 seconds or so for it to 'catch'. I checked fluid and it's ok. Shifter feels ok. Fwd gears are fine? Any ideas?

 

Add sea foam (the kind for trannys). Also check fluid level running warm in park. When you pullout the dipstick wipe clean bc it is hard to tell the level if fluid gets on the side of the inside of the filler tube. Check several times and look on both sides of the dipstick.

 

^What's that going to do?

 

It's been fine all day today. Fluid appears to be ok, though maybe not as red as it should be. I guess it couldn't hurt to do a fluid/filter change.

 

It's going to make sure the trans has enough oil for reverse to work properly.
The best way to check the oil (if you have the time) is to remove the stick, wipe it off, warm the engine first thing in the morning, put the stick in 6"+- from bottoming, grab it with two hands (so you don't bend it), and quickly bottom it and retrieve it. I assure you you will get an accurate reading the first time this way.

 

That goes without saying but no need to change the filter.

 

Welp, I went ahead and did a full fluid change/filter replacement. The pan magnet had no chunks, but a little sludge. The Fluid was closer to brown than it was red, and it was a quart or two low. Smelled old. No leaks that I am aware of. Took 21 quarts or so to get it all. Truck is new to me so I dont know when/if it had ever been changed..

Seems ok now, though it does take almost 2 seconds to get reverse when you first start the truck up and shift into reverse. After truck is running for a minute, shifting into reverse is immediate. This may be normal and I'm paranoid now. I remember a bit of reverse delay with my old F250 as well with the 4R100.

 

Mine has done it for years. It is more likely when cold but occasionally when heated. Putting it into drive first, then putting it into reverse makes it shift into reverse normally and then I don't see a problem for several days. Otherwise the transmission appears to work just fine.

 

Welp, maybe I spoke too soon. Over the past few days and about 100 miles, I've had a chance to compile some more accurate symptoms.

When cold, after sitting overnight, Reverse averages around 4 seconds to engage. Once it does engage, shifting back and forth through other gears, reverse is immediate and firm. I have zero issues in any fwd gears, ever.

If driving around town, and stopping to eat where the truck sits for an hour or so, I get the same symptoms.

Fluid is higher by about an inch when cold. In middle of hashmarks when warm. After sitting overnight, if I let the truck warm up for a minute or two, there is no change in reverse delay. Seems as if my drainback valve was leaking, letting it warm up would resolve my problem?


Changing the fluid definitely helped the delay in reverse on first reverse shift when cold. Could I still be low on fluid, even though within hashmarks when warm?

I'm not opposed to taking it to a trans specialist, but if there's any other things I can try, I'm all for them. Would trans issues generate trouble code to ECM? if so, there are none. The delay is just long enough to be irritating.

 

The fluid level probably helped more that the change.. Sounds like you needed a change BUT reverse requires some of the highest pressure to engage so it is just taking a few seconds to get it there (longer when low on fluid). How many miles on the X ?? If your sure about the level reading, I go the top line or a hair over (when HOT) on all mine. Also I know of the mixed reviews but I use Lucas trans fix. I've used the oil stabilizer in all my engines for 25 years, so now I use the trans no slip as well (never drove slushboxs till recently). I would add the Lucas & not worry about at all, it does not sound like you have a problem to me.

 

Truck has 135K easy miles. I guess it couldn't hurt to add another quart of MerconV. I've never believed in additives, but if it thickens up the fluid a tad, I dont see where the Lucas could hurt. I was surprised at the positive reviews this product received on Amazon.

 

In a system our size you would add 2 quart (the largest) bottles. If memory serves about $12 Ea..

 

Roger. I'll get my parts runner (the old lady) to pick up a few bottles on the way home.

 

I wouldn't add two quarts at once. Transmissions are VERY sensitive to oil level. Being too high is at least as bad as being too low.

Two seconds is the normal engagement time for a 4R100. If that's what you have it's normal. If you have a 5R110 it is too long.

 

Mark, thanks for responding. Now it averages about 4 seconds before engaging. And doesn't matter if hot or cold, it only matters if it's the first shift into reverse after sitting... If truck has been sitting for over an hour, same symptom. Once it does go into R, the rest of the time driving it is fine..

However, even when cold, if I let it warm up for a minute or two, I get same symptom.

If it was drainback valve, wouldnt warming it up give time for fluid to pump back into system?