JoeBoomz
05-06-2011, 10:12 PM
Hey guys, I wanted to post this here as I know a number of Marauder owners also enjoy the same engine in their Aviators :) Unfortunately the Aviator uses the same 5R55 transmission as the Explorer and Mountaineer and is prone to some common problems that will cause shifts to not happen or the transmission to slip out of gears. If you have a 5R55 with shift problems, read this before spending up to 3K on a rebuild.
We bought an 02 Explorer a year ago and a few months after buying it, we started having issues shifting from 1-2 and holding the overdrive gear. The OD light would start flashing and we would get a message saying "check transmission" on the trip computer. I got the fluid changed in the tranny ($120) and it did not solve the problem. In researching the problem and looking for solutions that wouldn't eat into my Marauder budget, I learned about the following issues that 5R55's can have:
- The valve body gasket can crack or break causing fluid to seep and pressures to drop. Testing if this is your issue is easy - drive as you would normally in 2nd gear and manually shift to 1st. If your vehicle "hangs on" to the engine and slows down (engine brake) then your gasket it fine.
I did not have this issue and don't know the cost of the gasket or the work that is involved.
- Shift solenoids can fail which can cause delayed shifts (like what I had) or shifts to fail entirely. Testing for this one is a bit harder; a code reader might tell you about the problem without having to take anything apart, but it's not always accurate. The solenoids can be tested with a meter if you take the pan off the tranny and check their resistance. Once you do that, it's a simple matter to replace them but refilling the transmission is harder and has to be done from the underside with a hose pump. The 5R55 does not have a dipstick tube that you can fill it from making it a bit more work.
I ordered a replacement (upgraded) solenoid online from Florida and got it shipped to Canada for a total cost of $220. I then paid a transmission shop another $300 to install it because I didn't want to go through the hassle with refilling it myself and was very busy with work at the time.
- Hardened steel servo shafts wear out the aluminum transmission casing due to a poor design decision on Ford's behalf. The hardened steel servo shafts are housed in bores in the aluminum transmission case and over time, the softer aluminum wears and the round holes turn oval-shaped. This allows transmission fluid to seep around the servo shafts and the servos move, allowing the bands to slip and in the case of the overdrive, let go entirely.
There are two servos in the 5R55 - an intermediate servo for the 1-2 shift and an overdrive servo that engages the overdrive band. If the ID servo bore is worn, the tranny will struggle to shift from 1st to 2nd if you are pushing hard on the gas, and will rev up to the rev limiter unless you let off the gas. If you start out slow it usually shifts without problems. If the OD servo bore is worn, your overdrive might work at slower speeds but the transmission will slip out of overdrive into the previous gear if you give it some gas or try to climb a hill. At faster speeds the OD won't work and you'll be running 3,000+ RPM's on the highway. :(
Ford's "official" fix is to drop the tranny, machine out the bores and add some hardened brass inserts so the servo shafts cannot wear any longer on the case. The quote for the transmission shop to do this was $2,500. I kept looking for a cheaper option, and I found it at the world's longest URL:
www.fordservoboretransmissionf ixsolution.com
The gentleman (Andy) had the servo bore wear problem, took some OEM replacement servos, machined grooves into them and added high quality rubber o-rings. The o-rings seal the servo shaft against the bore so fluid doesn't get by, while at the same time preventing rubbing of the bore and the shaft (hi CBT). The cost of these upgraded servos is $214US shipped. This fix worked and I was able to do it myself.
Without going into too much detail, the servos face outward and are located on the passenger side of the transmission adjacent to the passenger catalytic converter. The covers are held in place by snap rings and are a REAL ***** to get off. Andy recommends removing the exhaust and cat to make the job easier. Naturally I did things the hard way and only loosened the heat shield to work at them. It probably took me much longer and caused numerous scrapes and bruises on my hands, but I did not want to deal with difficult or stuck exhaust manifold bolts.
Once the snap rings are off it's a 10-minute job to change the servos. CBT, remember to use LOTS of lube when inserting the new servos because the added o-rings make clearances tight and you REALLY have to push hard to get them in. Getting the covers and snap rings back on is easy. Andy also recommends tightening bands when you're done as they will have been work from the servos slipping. I haven't done mine yet but it works great anyway.
I hope this post helps someone, perhaps even if only from a Google search. Hopefully it short-cuts you a few months in this learning process and allows you to select the fix that best applies to you to minimize your repair costs. Thanks to Andy for a terrific solution to a stupid problem - a few cents extra spent by Ford on brass inserts at the factory would have solved the problem before it happened.
Don't even get me started on the infamous "butt crack" that appears on the rear plastic applique of these vehicles because they glued plastic to glass and they expand at different rates! :P
We bought an 02 Explorer a year ago and a few months after buying it, we started having issues shifting from 1-2 and holding the overdrive gear. The OD light would start flashing and we would get a message saying "check transmission" on the trip computer. I got the fluid changed in the tranny ($120) and it did not solve the problem. In researching the problem and looking for solutions that wouldn't eat into my Marauder budget, I learned about the following issues that 5R55's can have:
- The valve body gasket can crack or break causing fluid to seep and pressures to drop. Testing if this is your issue is easy - drive as you would normally in 2nd gear and manually shift to 1st. If your vehicle "hangs on" to the engine and slows down (engine brake) then your gasket it fine.
I did not have this issue and don't know the cost of the gasket or the work that is involved.
- Shift solenoids can fail which can cause delayed shifts (like what I had) or shifts to fail entirely. Testing for this one is a bit harder; a code reader might tell you about the problem without having to take anything apart, but it's not always accurate. The solenoids can be tested with a meter if you take the pan off the tranny and check their resistance. Once you do that, it's a simple matter to replace them but refilling the transmission is harder and has to be done from the underside with a hose pump. The 5R55 does not have a dipstick tube that you can fill it from making it a bit more work.
I ordered a replacement (upgraded) solenoid online from Florida and got it shipped to Canada for a total cost of $220. I then paid a transmission shop another $300 to install it because I didn't want to go through the hassle with refilling it myself and was very busy with work at the time.
- Hardened steel servo shafts wear out the aluminum transmission casing due to a poor design decision on Ford's behalf. The hardened steel servo shafts are housed in bores in the aluminum transmission case and over time, the softer aluminum wears and the round holes turn oval-shaped. This allows transmission fluid to seep around the servo shafts and the servos move, allowing the bands to slip and in the case of the overdrive, let go entirely.
There are two servos in the 5R55 - an intermediate servo for the 1-2 shift and an overdrive servo that engages the overdrive band. If the ID servo bore is worn, the tranny will struggle to shift from 1st to 2nd if you are pushing hard on the gas, and will rev up to the rev limiter unless you let off the gas. If you start out slow it usually shifts without problems. If the OD servo bore is worn, your overdrive might work at slower speeds but the transmission will slip out of overdrive into the previous gear if you give it some gas or try to climb a hill. At faster speeds the OD won't work and you'll be running 3,000+ RPM's on the highway. :(
Ford's "official" fix is to drop the tranny, machine out the bores and add some hardened brass inserts so the servo shafts cannot wear any longer on the case. The quote for the transmission shop to do this was $2,500. I kept looking for a cheaper option, and I found it at the world's longest URL:
www.fordservoboretransmissionf ixsolution.com
The gentleman (Andy) had the servo bore wear problem, took some OEM replacement servos, machined grooves into them and added high quality rubber o-rings. The o-rings seal the servo shaft against the bore so fluid doesn't get by, while at the same time preventing rubbing of the bore and the shaft (hi CBT). The cost of these upgraded servos is $214US shipped. This fix worked and I was able to do it myself.
Without going into too much detail, the servos face outward and are located on the passenger side of the transmission adjacent to the passenger catalytic converter. The covers are held in place by snap rings and are a REAL ***** to get off. Andy recommends removing the exhaust and cat to make the job easier. Naturally I did things the hard way and only loosened the heat shield to work at them. It probably took me much longer and caused numerous scrapes and bruises on my hands, but I did not want to deal with difficult or stuck exhaust manifold bolts.
Once the snap rings are off it's a 10-minute job to change the servos. CBT, remember to use LOTS of lube when inserting the new servos because the added o-rings make clearances tight and you REALLY have to push hard to get them in. Getting the covers and snap rings back on is easy. Andy also recommends tightening bands when you're done as they will have been work from the servos slipping. I haven't done mine yet but it works great anyway.
I hope this post helps someone, perhaps even if only from a Google search. Hopefully it short-cuts you a few months in this learning process and allows you to select the fix that best applies to you to minimize your repair costs. Thanks to Andy for a terrific solution to a stupid problem - a few cents extra spent by Ford on brass inserts at the factory would have solved the problem before it happened.
Don't even get me started on the infamous "butt crack" that appears on the rear plastic applique of these vehicles because they glued plastic to glass and they expand at different rates! :P