Tranny issues?

[slravene]

OK, i need some tranny help. Sometimes (about 75% of the time) when i cold start my truck (start when not warmed up) the truck will do some wierd things. Backing out of my parking spot it will be fine, but when i go to put it in drive after i have backed out, when i put it in drive it will not engage immediately. It will engage if i let it sit for a few seconds, but if i try and quickly shift into drive and accelerate away...it will just flare up and ill have to let off the gas and it will slow the RPM and it will engage... . Im not sure whats wrong here, but it only does this the first acceleration after the shift. Im not sure what the problem is here, and im hoping that my tranny isnt dead. Can anyone lead me in the direction that i need to go about diagnosing/fixing this problem? Thanks.

 

[Glacier991]

First off, there can be quite a number of things that can cause this condition. The good news is that in the majority of cases this is not likely a rebuild issue, and in fact if you can live with it it isn't likely hurting anything, you may just learn patience.

The greatest probability is a low line pressure rise, causing delayed actuation of necessary components. You have not given me much to go on... mileage, how often fluid and/or filter changed etc. What is the condition of the fluid (color, smell, clarity)?

Gove me a little more info and I can walk you through some possibles.... I have to drive into the city today but will be back later this evening. Give me as much info as you can. Please.

 

[slravene]

ive got 120K on the truck. The truck however is in great condition. No problems with anything so far. Fluid has always been changed on a regular basis however last time i changed it, it was a dark red color and smelt burned. This was only after about 5-7K miles of driving. I just changed the fluid about 100 miles ago, and after this change was when i started having the issue if i remember right. The truck isnt driven much since I am in college, but im just lost as to what would cause it to sometimes engage and sometimes call for a RPM of about 1500 in order to engage... Any other info you need?

 

[Glacier991]

This is a case where knowing what our pressures are could tell us a lot. The 4R55 and it's newer cousin the 5R55 use an electronic pressure control solenoid which can adjust internal hydraulic pressures in the transmnission under computer control. A pretty cool idea actually. That EPC solenoid can wear out, and when the pressures are too low, it can allow slipping bands and clutches and can manifest itself in other ways, such as delayed servo fill and engagement concerns.

It costs about $110. If you want to make a more perfect diagnosis you will need to invest in a pressure gauge. Otherwise, I'd suggest you read the 5R55E Valve Body Rebuild Diary and consider rebuilding your valve body and replacing the EPC solenoid. The Superior Kit is for both the 5R55 and 4R55 valve bodies. They are "nearly" identical.

It really does sound to me like your pressures are low. I'd fix it and not keep driving it until I do. If you glaze your bands you WILL be facing a rebuild.

Hope this helps.

 

[slravene]

How hard of a rebuild is that? Ive got plenty of tools but have never taken apart a tranny, nor have i any transmission experience what so ever. Looking through that rebuild diary, i was almost completely lost by page two... How much would a shop charge me to rebuild just the VB? Is that my only option?

 

[jobjumper]

Whats the chance of informing NHTA and try to force a recall on these trannies. No transmission thats been taken care of should go like this. My O/D light started blinking at 93,000. My wife's Sable is 142,000 miles and no problems, those transaxles are notorious for being junk. I'm not happy dudes.

 

[caldi55]

That just started to happen to me
i checked my fluid level when it first happened and it was low so I thought that would fix it. But now the levels fine and when its really cold out it still does it. I find that plugging in my block heater on days when its below 20deg F. helps

 

[tenikiwon]

My does that only in really cold weather. If I let it warm up it's fine. Usually when I suspect it I try to move forward and rev and it one doesn't work I put it in N and rev it for a bit then try again.

My tranny has over 160, prob closer to 180 or 190k on it and hasn't had the fluid changed in over 100k, and I've been thru pleanty of water, etc.

recently when I was towing my zuk I got the flashing OD light. This had happened two other times, both in cold weather with a heavy truck but no trailer.

The first towing day I forgot to put OD off and it came on after getting up to speed on the highway, the second day it wasn't on at all.

When I moved to VA and towed my Zuk the OD light flashed the entire way. I had it checked after I got here and they told me it was excessive torque conv slippage. I had them reset the code and haven't had it come back on.

...for what it's worth...