5R55E RPM's don't increase in 3rd gear

[andy123]

The tranny shop I took my 01 Explorer XLS to fixed an electrical problem of tranny slipping in 3rd gear 1 month ago. Since then, the tranny goes into 3rd at 40km/h, RMP's drop from 2400 (in 2nd) to 2200 in 3rd...and RPM's stay at 2200 from speed of 40km/h to 60km/h...then increase to after 60km/h before going into 4th gear....then OD. I showed the tranny shop this and another mechanic....they both told me since there is no slip and no codes everything is good and normal......

I'm not happy with their answer....so any ideas here what this irregularity could be? Or is this normal and I'm worrying over nothing?

It seems like the RPM's even though they dropped 200-300 from 2nd to 3rd don't drop enough...and the tranny is somehow taking its time to fully engage and catch up while vehicle is increasing in speed.

 

[gavin]

not taking the tach reading into account, can you hear the engine speed increase?

I honestly don't see how the vehicle could accelerate with no increase in engine speed.

 

[andy123]

Is it possible in 3rd gear (3rd gear on swap-shift tranny is actually 2nd simpson gear X an OD gear) that the rpms stay the same as its engaging, while engaging making the vehicle go faster? So it stays same rpms as it goes from 25mph to 40mph......? Could the torque converter be putting out more speed as the engine stays same rpms?

No mechanic or tranny shop I talked to has answer why my vehicle would do this.

 

[gavin]

if this were the case, you would be having MASSIVE convert clutch slippage, which could destroy the torque converter and/or transmission fairly quickly.

How does the transmission fluid look/smell?

And I'm still curious as to wether or not you HEAR the engine speed increase.

 

[andy123]

The rebuild I had was 5,000 miles ago. The fluid looks red and doesn't smell burnt at all. I can not hear the revs increase, when the tach is stuck in 1 place while speed increasing in 3rd, it seems to be good indication of what the rpms are.

When the 2nd to 3rd shift happens at about 30mph, the rpms drop only 200-300 rpms, does that sound normal?

 

[manaen]

what happens if you pull out hard, the 5r55e is a close ratio tranny, on a slow pullout it can operate so smooth that you almost don't notice the shifts. The variable pressure in the tranny due to the EPC makes the tranny very smooth on light throttle. However when you stomp on it, you should be able to feel and hear every gear, of course I wouldn't recommend holding it much past 3rd since you will be going quite fast.

I have my 5r55e setup for towing, and even with the heaviest shift springs, it shifts silky smooth with light throttle.

Give that a try and let us know how it feels.

 

[andy123]

When I accelerate slowly it shifts nice. It goes into 3rd at about 20-25 mph and the rpms drop from 2200 to 1700. It's when I try to accelerate faster. Second gear winds up to 35mph at 3000rpms, and when it goes into 3rd the rpms only drop to 2700rpms, and stays at that point until about 45-50mph where it drops into 4th at 2200rpm.

Maybe I will just baby the thing since that's what I consider a normal shift. This tranny has given me so many problems with the electronics and the fact no tranny mechanic I talked to can figure it out.

My 1st Explorer was a '91 standard 5speed. That tranny shifted smoother than any other manual I owned. I will never buy another auto tranny again.

 

[manaen]

It's really pretty normal, the thing is once you get to third gear the ratios are such that from 35 to 45 you will see little rpm difference. The goal of a well tuned tranny is to keep the engine in it's optimal power curve to produce the most efficient torque. For all it's flaws, the 5r55e is a really great shifting tranny, and it is also the reason the SOHC is faster than the V8 in stock form.

But just in case you are having problems, I would just monitor it closely. check the following.
Does the fluid smell burned at all? and does the shift from 2nd to third feel solid? have you checked with ford to see if there are any updates for your PCM. They do have a shift update that came out, but the only way you get it is if you ask for it, so most vehicle did not receive the update. I had mine done when I had the infamous cruise control recall done.


I would also highly recommend that you add an additional stacked plate tranny cooler. The 5r55e runs very hot, and it get's to those temps very quickly. The electronic solenoids in the valve body are very suseptable to dirt in teh fluid which cause problems with shifting. Ford actually had a TSB out that also recommended adding an external filter after the coolers in the return line for the fluid. The purpose is to catch any debri before it re-enters the tranny. I would also recommend you go with full synthetic fluid. It is much more resistant to thermal breakdown. Also (just one more) when you had the tranny rebuilt, did the guy perform the Ford updates to the valve body, and install a shift kit (like a transgo etc) to address some of the short coming of the 5r55e? if not they are pretty important IMO

If you don't know about the updates check out the 5r55e rebuild diary in the transmission section of the forums!!

 

[andy123]

Thx for your replies, manaen. If you say that the rpms are normal to go up very slowly from 35 - 45mph when accelerating, so slow that its barely noticable, I will take your word on it and live with it. The rebuild was done 6k miles ago. The rebuild I don't think really needed to be done, my original problem was tranny slipping out of 3rd. Even after the rebuild it did the same, the whole original problem was electronic. The tranny shop put in a "kit" that their supplier sold them. He told me all seals, valve body, clutch pack, solenoids, and torque convertor was changed. After I brought it back he dropped the pan and fixed something with the electronic (he wouldn't really say what, said he wasen't sure what caused the slip).

Since then I noticed the different shifting (different from before rebuild, what I was used to) , and in 6k miles the fluid doesn't smell burnt at all, and is light red.

Anyways, I'm off to cottage for some bass and walleye fishing for a week....take care.

 

[manaen]

Anyways, I'm off to cottage for some bass and walleye fishing for a week....take care.

Excellent!!! Largemouth or smallies? I'm gonna try to get some of that in this weekend as well. these darn home projects have been really cutting into my fishing time