08 Torqshift Delayed/Harsh Reverse, no OD

Buddy_M · February 10, 2011

OK guys.. I am not a transmission tech by any means, and finally opened my first transmissions (99 4R100) about a month ago out of my own trucks to overhaul them. Since then, I have a company that I have done some other maintainence for brought in a truck and asked me to check it out. They got it stuck in the snow and tried to rock it out, after that, there is no OD and reverse is harsh when it finally engages around 1500-2000rpm. I get a code 0766 and 2703, direct clutch faults.

I also had hooked up my pressure gauge to check line pressure, in idle all pressures were close to the spec listed in the service manual. I then checked line pressure at stall, and all pressures were high, and after then shifting back to park/neutral, line pressure would then jump to about 280 and remain there until I shift back into any gear and it would drop to the idle spec. I am thinking a regulator valve or solenoid issue, and possibly a clutch pack issue for the harsh engagement?

This is now the 3rd transmission I have ever had to diag and my first 5R110, and am just looking for some kind of insight on issues they have. I am leaning towards pulling the transmission to look at the direct clutch and want to know if I am on the right track or if I'm just confusing myself into thinking the wrong thing.

Keith Browning · February 10, 2011

I would think that the failure occurred after engaging reverse and drive repeatedly they more than likely damaged a clutch assembly, a snap ring... I would perform the solenoid checks, pull the pan and inspect for Ddebris. I have a feeling you will be tearing this one down. Most of the Torqshift failure I have seen were reverse clutches, snap rings and failed planetary assemblies. We don't see many Torqshift problems any more and that is all I have to offer.

Jim Warman · February 10, 2011

Do you have all other gears? Clear codes and take it for a drive cycle. Monitor GEAR# (which will be the gear commandewd by the TCM), GEAR_RAT (the ratio the TCM expects to see - this is the actual physical ratio of the trans) and TRAN_RAT which is the transmission ratio computed by the TCM using TSS and OSS signals.This will alert you to "missed" ratios and and slipping friction elements.

The reason you want to clear codes - the TCM will not attempt to make any shifts it feels are not "viable"... kinda like going into a self preservation mode. Clearing codes will have the trans attempt shifts that it might otherwise miss when codes are present. The presence of some codes may also affect the trans pressures you see during testing.

Once you have a clear idea of what shifts are affected, you can drop the pan and inspect for debris. After that, drop the main control and do an air test using 307-457 test plates....

Now... I'm a fussy old !?@#%! and I like to know exactly what I expect to see once I go into any transmission.... opening these damned things up and praying you will find what ails it can be time consuming, frustrating and even be overlooked during component inspection.

Like Kieth has stated... it's a pretty fair bet you are going to find a concern with the direct clutch since this clutch is applied in reverse, 5th and 6th gears... Important to remember - when TFT is above -15C the trans shifts 1 - 2 - 3 - 5 - 6. Direct clutch failures are rare in this puppy (my humble experience). And you still want to have a good idea about the rest of the trans before you commit to the teardown.... When the trans is scattered across the bench is a bad time to start wishing you had checked something before you dropped the pan the first time.

I've seen several 08s with reverse clutch failures... been a while since I had a 5R110 open but I recall that the reverse clutch was updated with a rather large chunk of the stack being replaced on failed units...

HTH

Adam_Dodson · February 11, 2011

What Jim said...also if they had it stuck I'm betting the TFT was high enough that anything other then a complete overhaul would probably not be a good idea...Im guessing this is a retail repair. If it were me it would most likely get a reman. Let the rebuilder carry the warranty.

Buddy_M · February 11, 2011

Jim, I had cleared codes and test drove it, however I didn't monitor any of the pids you listed, however, it still had the harsh reverse and no OD. This same truck about 3 weeks prior I had put in a new transfer case because they got stuck and blew the transfer case into 2 pieces, and test driving after installing the new transfer case indicated no transmission problems at that time.

I should have some time tomorrow to check what you listed and get a better idea of the failure, and this is a retail repair being way over mileage from travelling from Texas to ND multiple times and being oilfield related. If it needs to be opened up, which it most likely will from how its looking, they want to know what the cause of failure was before deciding on how to proceed. The hard part for them is they want all repairs cost capped at no more than 1500(except in certain circumstances), except for certain priority vehicles, and this kind of repair will certainly be more than that, so we'll have to see how far they want to take this.

cbriggs · February 11, 2011

Quote:

like to know exactly what I expect to see once I go into any transmission.... opening these damned things up and praying you will find what ails it can be time consuming, frustrating and even be overlooked during component inspection.

This is the best advise on trans repair anyone can give. It is way easier to duplicate and test a problem, have all the info and research done ahead of time, and know what you expect to find wrong inside. Once the trans is in 500 peices on the bench its too late for testing, and it would definatly suck to have to put it back together to do more testing. Have a clutch and band apply chart, and a solenoid apply chart handy, and see what all of your problems have in common.

I have had a few direct clutches smoked on these, all were 6.0l that involved a chip of some sort. Have also had a few reverse clutch failures and one reverse piston seal fail.

Jim Warman · February 11, 2011

For the worlds best apply charts for the 5R110 (and a few others) visit HERE . Consider purchasing their software. The author is a pretty good guy.

However... what you are really after is in the "downloads" section. Apply charts along with paths of power... Some of you might recognize this stuff...

Buddy_M · February 12, 2011

This morning, I had some time to look at it, and dropped the valve body and air tested. Low/Reverse, Direct, and another clutch assembly(Don't remember which one off the top of my head) have a terrible leak coming from them. No significant debris in the pan, but it certainly looks like it will be coming apart now.

Keith Browning · February 12, 2011

You know, I have been fooled by supposed air leaks when air checking. Ideally you don't want to hear leaks but remember some pistons have those vents with the balls in them. What is important is that you use air regulated to the recommended pressure and that you hear a solid movement as the clutch applies. Obviously not all clutch pistons have valves so you can see how that can screw with you. I am glad to hear that you are air checking.

I now have an 07 in the shop with an intermittent delayed and harsh reverse engagement. Posted Image

Jim Warman · February 12, 2011

What Kieth said... When air testing a trans, you are listening for that <clop> sound as a piston moves to it's end of travel. Listen to no other sounds.

Like air testing a 6.0 HPOP system... once you get all the oil out of the rail, you can get air to come out damned neart everywhere.

Good judgement comes from experience..... unfortunately, experience comes from bad judgement. The very first auto trans I ever repaired was a C-6 out of a 67 Fairlane 390 CID that belonged to a very good friend. We put it together with the low OWC backwards.... Posted Image

robsmth41 · December 9, 2011

I saw this same issue at my last shop. tranny had about 39k on it in an f-350 dually. trying to recall the exact failure is evading me right now, but all of the bands were shot and the case had fractures all across the machined surfaces. Sorry i can't shed more technical light on it, but as an advisor my info is limited.

Keith Browning · December 9, 2011

I saw this same issue at my last shop. tranny had about 39k on it in an f-350 dually. trying to recall the exact failure is evading me right now, but all of the bands were shot and the case had fractures all across the machined surfaces. Sorry i can't shed more technical light on it, but as an advisor my info is limited.

As a service adviser I recommend that you spend more time in the shop when you can and look at what the techs are doing. Look at the parts and assemblies. Ask questions. Doing that will give you better product and technical knowledge that will help you do your job and make you a better adviser. Point being, there are no bands in a Torqshift transmission.

You might also consider taking some of the web based courses that we take. Knowledge is power!