Mike Up

How's that so? The Mustang has 320 lbs of torque yet uses the 5R55S. 55 = 550 / 2 = 275 ft/lbs. That's 45 ft/lbs. shy of the engine output. Have a good one.

OK, I finally found out where I heard the 2008s had the 6R80. It was directly from Ford's website here. It appears that all the above now have the 6R80 for the late 2007 model year and 2008 model year. Nowhere on Fords site do they reference the earlier Explorer 6R60 transmission or th earlier Expedition 6R75 transmission. My TSB bulletin even referenced the 6R60 model number. From what someone stated, the transmissions are all the same but differing the torque converter for midsize and fullsize trucks. Perhaps the 6R80 is a general model number. Have a good one.

All he was stating that Ford was ridding themselves of the CVT because of oddities in their operation to most folks. They were replacing them with 6 speed trans for equal performance benefits and fuel mileage. I don't believe they omitted the 1 way clutch on those models as they all get great mileage already, but they may have. Have a good one.

That's the thing, it does shift fine when slowing smoothly to a complete stop and then accelerating. What is not normal is the characteristic of lacking a 1 way clutch. It shifts to 1st at the last moment. It won't shift to 1st until the vehicles axles have 'stopped'. If the vehicle is even rolling very slightly, you'll feel a slight bump to 1st. The only opposition I found to this is when coming to stops very slowing. It seems if the vehicle is at a very slow speed for a set amount of time, the trans will shift to 1st. Sometimes I can feel this shift as it's very vague and others times I can't. Now if you do a hard stop, and just come short of completely stopping, and accelerate aggressively, you'll feel a more pronounced bump. The worst case situation is that the body is still rocking front to back from the quick stop, and you come just short of stopping with barely any rolling, you'll feel a driveline backlash when acelerating. This can feel like a pronounced bump to a stuttering. If you simply come to stop smoothly and slowly, and stop completely, the transmission shifting is never felt and feels smoother than many other transmissions. The negatives are directly based on the transmission omitting of the 1 way clutch where 1st gear down shifts can't come sooner without a pronounced bucking where you feel like you slammed on the brakes and then a lurch. Just as if you shift a direct coupled "manual" transmission with little clutch slippage. With a manual you can get away from the bucking by slipping the clutch engagement. With an automatic , "according to the Tech", the clutch pack can't slip or extreme heat will result and will damage the transmission. A precise and firm engagement is needed in an automatic transmission's operation. I never had any downshifting issues while braking with the 2008. The last program simply had the 1st gear downshifts slamming. I don't know how the last TSB program corrected that 1st gear take off shift shock but it did when acelerating from a 'near' stop. I honestly believe it limited the amount of time the gear took to shift, from when the acelerator pedal was pushed. Shortened the 1st gear shift time so it was less likely to slam into 1st from added accelation, but I could be wrong. The whole problem of this transmission is the lack of a 1 way clutch. Reason, to save FUEL ECONOMY. All auto makers are required to have a much higher average MPG across their entire line by a certain date, and is required by the EPA. This transmission is to provide their EPA requirement. If they threw in the towel, and kept the 1 way clutch, it would be no different than any other vehicle where 1st gear could shift early and not engage until the rpms of the axle side matched the rpms of the trans side. Allowing you to coast or over run until the rpms matched. BTW, GM's new 6 transmission will also lack a 1 way clutch and I can almost bet that Toyotas does also. They most likely just got the shift stradegy done correctly the first time, although theirs have trans failures and tons of transmission problems. Toyota more reliable?? How about no reliability! I went through the same crap with very unreliable Nissan Fullsize 1/2 ton Titan. Drivetrain was crap and failing. They also cheapened their paint and assembly processes. Had problems on the Titan and new Pathfinder, so all my truck purchases will be either Ford or Dodge. Have a good one.

Sorry I was wrong. The ink was smunged and I thought it read 6R80, it is the 6r60. Sorry, have a good one.

Mine doesn't do that since it's a 2008. Mine doesn't shift to first at stops unless you come to a 'complete', none rolling stop or come up to a stop slowly. Either way, it doesn't slam, only a bump that sometimes can't even be felt. That bump gets amplified though when a hard stop is done and the vehicle rocks from the stopping and your accelerate before it stops rocking. The bump then become very pronounced with a quivering. Have you driven a manual transmission based vehicle? I have driven class 7 heavy duty rigs, light trucks, and sport cars. I never shifted back to 1st, then engaged while slowing unless I needed to accelerate. You need a lot of clutch slip to keep the vehicle from bucking. The reason, because of the short ratio of 1st gear. That's why you can use 1st gear to almost stop your vehicle when using it for engine braking. Have a good one.

So what's up with a different model transmission on the 2008s. The 2006s and 2007s with the 4.6L seem to have the 6 speed auto 6R60. I have the 6R80 transmission in mine. I heard the 6R80 is the same trans in the Expedition so did they beef up the trans for 2008?? Have a good one.

Well I finally talked to the Transmission tech at the dealership then reseached his explanation and he's correct. This 6 speed is a new beast, actually a high torque replacement for the CVT. The transmission, as I would assume most know, is actually geared terribly for mileage. It has 5 shorter gears than most 5 speed autos but shares the same ratio on the overdrive. Hence, the mileage should be worse, but Torque multiplication for performance and towing should be great. To acheive this and gas mileage, along with smoother shifts, some redesigns had to take place. The torque converter which has a "1 way clutch", now has no one way clutch. That clutch allowed the over-run so while the vehicle shifted to the shorter first gear, the transmission would 'coast' and not lurch as it would do with a 'manual' transmission. Well this transmission is more like a manual by not allowing over run. It offers all the benefits of a direct coupled manual transmission but with the auto shifting. You now don't have drive loss through a torque converter. Since the design is now different, the clutch packs can engage at lower RPM which allows more efficient performance. The downside is that since the trans will not coast now when it shifts to 1st, 1st gear must be shifted at the last moment, which is at a stop. With quick stops which are followed by quick take offs, you will feel the trans bump into 1st after accelerating. If you wait a moment, the trans will shift into 1st before you accelerate. To gain the efficiency to get higher mileage yet get the performance of a 6 speed manual transmission, you have to deal with last minute 1st gear shifts. Obviously the first program wasn't right so the later TSB delayed the shift to 1st and the harshness of it. I also found the bump getting harsher on certain stops and goes where it slammed and spun the tires. I mainly do a lot of highway driving. The trans needs 3 - 4 days of stop and go driving to learn the driving habbits. I didn't give it enough time with my 4 days because it was mainly highway driving. So far the trans is feeling good. However, when driving in a parking lot, the truck will feel as it has a manual transmission in 1st gear. There's no more coasting or as they call it, over run. Look up these new 6 speed trans and the 1 way clutches and you'll find this information on the net. Ford is introducing this 6 speed in the F150 as an option only with the 5.4L and GM and Toyota are also using this technology. Toyota is having a lot of problems with their 6 speed trans in the Tundra right now. A lot of noise and vibration at certain rpms and Consumer Reports rates the reliability of the new Tundra as bad as it gets. Ford also has replaced their previous CVT driven vehicles with the new 6 speed transmissions. Very good performance with good mileage of a manual, but with auto shifting. This looks to be the future with government mandates on fuel economy. Am I completely satisfied with this trans? NO, but it does have some good performance benefits. What I have learned now that the trans has been through the learning curve is a few oddities directly related to the lack of a 1 way clutch. BTW, all the new 6 speed automatic transmissions will lack a 1 way clutch and act just like fords. Do a search on the web. GMs definitely will not have a 1 way clutch and will be direct coupled like Fords. Do I like this, hek no, but it does offer performance advantages while maintaining standard fuel economy. I have the latest TSB on my 2008 XLT 4X4 4.6L 6 speed auto is TSB 08-4-16 released 2-6-08. What I've learned is that the program is based on time and shaft rotation. If you come to a smooth stop with no little or no body sway, the slow acceleration and stopping will give enough time to the trans to shift to 1st smoothly before you stop. If you drive more aggressively than a grandmother when going to work as I do, I make my stops and goes a bit more abruptly than grandma. With slowing quickly on a level surface that causes little body rocking when coming to a harder stop, you'll simply feel a bump upon acceleration. This is caused when you don't come to a complete stop. Sometimes I thought I was stopped but even the slightest roll will cause 2nd gear to stay in until acceleration. Now if you wait until you're fully stopped, there's no bump. Now the worst case is when I do a quick stop, quick start, on an incline or a really hard stop. Both cause the vehicle to rock. Add this motion to a start where you feel you're stopped but just barely rolling and the transmission bumps to 1st at the same time the body is still rocking. The rocking of the body at the same time the trans tries to shift causes some driveline stress and seems to cause a quivering bump that can be harsh. I feel that we all have the same trans issues but some of us drive differently and the transmission's characterists will show up differently under our differing driving. The transmission will shift perfect if you accelerate slowing to a stop, stop completely with absolutely no roll, and then accelerate. You have to drive this as you would a manual. Think of the shifting very similar to a manual since we now have a manual essentially without the 1 way clutch to coast/over run. I'm not fond of this and wish they could have the 2-1 shift a bit sooner but according to the Ford Specialist my Tech spoke with, not many are affected by the new shift stradegy as were with the hard 2-1 as was previous. Ford definitely knows about the problem as do the service techs. This is not a standard transmission by their definition and it will not shift as a normal transmission. It's to give the same benefits of a CVT transmission with more normal characteristics and more robust handling as for pulling trailers. I was instructed that I could periodically check back to see if a new TSB was available since I have the vehicle in warranty. Hope this helps, have a good one.