4r55e/4405 Rebuild Notes

[95beater]

With 157,000 miles on my 4r55e, it stopped shifting from 1st to 2nd and the seals on my 4405 were leaking pretty badly. It was apparent that I needed at least a transmission rebuild and some effort to address the leaks from the transfer case.

Here’s what I learned from my transmission shop (members that know better feel free to post). Some of these items are address in other posts, but I figure it would be helpful to somebody having them all in one place.

· A few weeks before the transmission blew up the o/d light was flashing and the torque converter was cycling on and off (surging) at highway speed. I suspected an electrical problem, such as the throttle position sensor (TPS), but I was too lazy/busy to check it out. According to my trans shop the TPS was bad, likely failed to control line pressure, and could have caused the trans to die. I’ve never heard of this before, but I suppose it makes sense.
· Many high-mileage 4405 x-fer cases cannot be rebuilt/made to stop leaking without replacing the case halves. According to the shop/other sources, the case bearing races/shift rail mounts wear out and cannot be fixed without significant machine work. This shop replaced the halves with machined units from this vendor: http://www.omegamachine.com/html/BW4405_rear_case_repair.html . The total cost of the rebuild (case halves, bearings, and seals) $550 installed
· A band broke in the trans and the torque converter was wasted. The new trans feels great. It’s like a new truck. According to the trans shop, the parts available today to rebuild the 4r55e eliminate many of the old drivability problems, including weak 2-3rd shifts and slow to go into D and R. It’s much smoother and fuel economy has gone up about 1-2 mpg. Trans rebuilt and installed, $1400
· Make sure the shop tests the transfer case operation in the shop and on the fly. My shop only tested the 4x4 operation in the shop, but I testing it on the way home while moving and it would not shift on the fly. The 4x4 Hi and Lo lights would flash 6 times after about 40 seconds. According to the shop, they boogered up the rear driveshaft speed sensor, which would not allow the transfer case to synchronize.

 

[Glacier991]

I will be posting pics next week from Omega... here in Sacramento where I live. I briefly described their 4405 fixes, and hope to get you some pics to clearly illustrate what they do. $550 was a very reasonable price on the TC and if you got af ull rebuild (not just soft parts) for $1400 that was also pretty good.

 

[95beater]

Pictures of the Omega halves/repair process would be great. I've got an engineer from Borg Warner in my MBA class. I’m going to bust his chops this Saturday for the 4405 shift rail design. I’ll send him a link when you post it.

As far as the "full" rebuild on the TC, they did not replace the clutch. While I live in Illinois, my Explorer was used as a grocery getter by a family in Tennessee for 114,000 miles. With their mild winters and the lack of off-roading, I suspect that the shop's assessment was correct; that the clutch was ok.

After the shop's quote of $2450 for the repairs, I drew a line in the sand of $2100, cash, for everything (TPS, tax, rear main seal, ect). The cash part went a long way. If I had charged it, and paid it off in 12 months I would have paid $350 more + $300 or so in interest. If others use my "line in the sand" approach, make sure you get in writing what they will replace and ask for the old parts back. But also keep an open mind. I would have rather have a shop put in the right parts under a "change order" than put a near-dead part back in to keep it under the quoted price.

As far as the good prices, I have to thank everyone on this fantastic site for the superb technical information available. Based on information available on this Site, I basically figured out what was wrong and the price range for the repairs. This is honestly the best and most useful “member driven” car site I’ve ever used. Between my fleet of Rangers and ½ ton Chevy’s at work and my wife’s annoying Sienna minivan (bought new in 2005, poorly engineered electrical system ), I’m constantly looking for car information on the web. While other Sites let me down, I always find the answer here for Explorer/Ranger issues.