Transmission/ solenoid problem?

[c rosso]

I'm back.
I had a transmission problem (no reverse) a few weeks ago, and talked to several of you then. I ended up replacing my transmission with a full rebuilt one to the tune of $1500 ( in Canada, so cost more $ then U.S.) It rode much better with the new tranny so I figured it had been going for awhile.
I still got a slight clunk when it was cold and I put it in reverse. This morning I discovered a problem with Drive. No pickup, could almost floor it without it taking off. Also had the check engine light come on. I took it directly to my mechanic, they test drove it and agreed the transmission was slipping. The scanner showed a 'factory code' for the check engine light.
I left it with them, I have since called and they 'think' it might be a loose or broken wire, or a solenoid. Would either of these things not be visible or checked when the tranny was removed and replaced?? They are also concerned about the tranny 'reverse' clunk. I am slow (and yes, I'm female) when it comes to mechanics....I'm feeling a little 'ripped off '. My truck remains in the shop. The rebuilt has a warranty (tho not very big). Help please.

 

[Glacier991]

A "factory" code merely means it is not a standard OBD-II series code, but one of the proprietary ones used by the mfgr on their products. It would be helpful to know that code. The clunk may be something as simple as a u-joint.... There are a number of things that could produce your problem... most involve a failure of line pressure somewhere/somehow. (The list of possibles here is rather long).

[I use the term "line pressure" a lot... let me define it for anyone who wonders what the heck I am talking about. The transmission quite literally operates as it does because there is fluid under pressure being routed around by the valve body to actuate various parts at the correct times. This fluid makes the auto transmission a hydraulic device, and it is a wonder how anyone every figured this all out. Anyway, I digress...the hydraulic pressure is created by the pump and then controlled by a regulator valve in the valve body.- and, importantly it can be measured and conmpared to "acceptable" readings. If the pressure is too low, the needed "oomph" to actuate certain parts may be lacking... hence... no movement or delayed movement, slipping shifts etc. When you suspect low line pressure the first smart thing to do is measure it. I have a thread on how that is done. In the 5R series (which you have) you can also test EPC (Electronic pressure control) pressures in addition to line pressure. Often it is about half of line. Once you have found low pressure the trick is to isolate why. It can be a pump problem, a seal problem, a gasket leaking problem, a valve body problem.... and/or a few other things I'm too tired to remember. A pressure gauge can help isolate where the problem is. I am convinced it is a tool anyone working on trannies should keep handy in their tool boxes.]

 

[c rosso]

transmission/solenoid problem

Thanks for all the info Glacier 991.........not sure I got all of that (remember I said I was pretty duh when it comes to mechanics ) , but got the importance of 'line pressures' I talked to my mechanic today and he has sent my truck to a transmission shop (at his expense) to find the problem. He says they are checking the line pressures, no one wants to have to take the transmission out and start all over if not necessary. You see, the rebuilt transmission that was just put in was done by a 'friend of ' my mechanic, who does trannys officially for a dealer, but also does extras (like mine) on the side.....and of course, charges less than you would pay at the dealership. So the tranny shop checking my truck now, is not the same people that put it in.
Its very frustrating.....