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cold transmission slips every morning

29K views 14 replies 7 participants last post by  dodgedawg 
#1 ·
Hey all,

When my '97 auto tranny is cold in the morning and I first take off it will slip going into 2nd gear. I have to stop, put it in park, then in drive again and it will take off again. We go through this fun chain of events every morning until after the second or third time it will finally run normal, then never do it again for the rest of the day. It does it less if I really warm the truck up for a long time but at these fuel prices...

Any ideas as to what this could be? And on the topic of the transmission, is it normal for the torque converter to 'thud' the whole truck when it kicks off?

Finally, could any of this have to do with my horrible fuel mileage (about 10)?

:sofa
 
#2 ·
In general, I dont have a specific answer to any of the above questions, though when I start my truck in the AM here (socal) usually if i take off RIGHT away, it will lurch into first right when i drop the shift lever into D ( and this is on a VERY slight uphill incline). If I give it 3-5 minutes to warm up (usually around end of week, IE thursday or friday) it will shift into gear smoother and not hesitate when I drop the shifter.

Granted this problem has really only been aparent since I ran my tranny low on fluid then changed fluid and filter, it still kinda is odd to me, though perhaps a 47RH guru will pop up on here and have some answers to the situations we are both facing-

Oh, and on any given morning (for anyone whos going to post answers) the temp here when I startup is between 40*-55*F.
 
#4 ·
will swap filter & fluid

Changing the filter and fluid will be what I do next. On the stick it doesn't look real bad but it's not new either. I once saw in a post another guy complaining about this same thing but couldn't find the post to see if he got to the bottom of it. Something was mentioned about 'pressure' taking too long to build...?
 
#5 ·
I would change the trans fluid and filter first. Could be as simple as that.

Does the trans start in 1st or 2nd from a stop? Go to 1st on its own or manually? Either way, there is a chance you might need to replace the governor pressure sensor and gov. press. solenoid. ~$100 a piece. Have to drop the valvebody to change them out.

The stock transmissions don't flow much oil in park. That is why you have to check the level when it in neutral. The T/C drains back overnight sometimes, so try putting the trans in neutral for about 30 seconds after startup. That will fill it back up.

Cold oil will cause the trans to feel like it grabs when you put the trans into gear. Once it gets warmed up, it won't do it as much. It is even more so when you have a built trans like mine. The T/C is quite a bit tighter than stock, and pulls harder when in gear and not moving. I can roll uphill with a loaded trailer at idle sometimes. :D

NukleusX- dd has a 47RE, not a RH, so the cause might be different than yours.
 
#6 ·
thanks

It's getting the transfluid and filter change tomorrow. I wanted to do it myself today but got under there and there is no drain plug?! Do I have to drop the pan or is there some sneaky way to drain it from a hose somewhere?

It does take off in 1st and shift back down to 1st o.k. I will warm it up in neutral some and see if that and the fluid/filter change fix it. Once it takes off out of the driveway there isn't another transmission issue the rest of the day...that fluid must make it's way everywhere.
 
#7 ·
Ya, no drain plug. Could oder an aftermarket pan with one, or get a drain plug kit from B&M.

No real good way to drain it. I remove all but one bolt on a corner, just loosen the last one and support it with you hand. Gently let it tip down and hopefully most of it hits the pan. Just don't let it hang there. Could bend the corner.
 
#9 ·
progress

It reads full on the stick but maybe the stick isn't giving me a true measurement...when yours was low did it read low on the stick? Is there major harm if I slightly overfill?

bmoeller, warming it up in neutral stopped it like you said! No slip at all after only 60 seconds warming up in neutral...good call. I still want to get to the root of it so I will do the fluid/filter change (as soon as my 8 month old lets me).
:pointlaugh
 
#10 ·
There is a check valve on the tranny line to cooler that is supposed to keep fluid in the TC. This valve can stick. Shut = bad ju ju, no fluid flow. Open = TC drains down overnight giving your truck "morning sickness". Putting it in neutral for a bit fills the TC again and off it goes like it's supposed to. Some have removed this valve to prevent it sticking shut. Just need to remember to let it sit in neutral for a few seconds on first start after it sits for a long time.
 
#11 ·
tran oil/filter changed

WAY overdue...even though redish on the stick the oil looks just like motor oil in the drain pan. The filter looked completely brown and clogged and there were metal fragments stuck to it as well as infused in the oil. That magnet in the bottom of the pan, presumably to attract metal fragments was big and fuzzy like a donut with muck and fragments. Amazing I didn't ruin the transmission running it like that...pretty lame given the whole thing took less than an hour and $25. The transmission shop a block from my house wanted $149 for 'service' which turned out to be nothing more than fluid/filter change.

I'm sure it will run better now, on the test drive I felt the torque converter pull MUCH stronger uphill...I'm hoping this was part of the reason my MPGs sucked so bad. Will post back and report if this cured the early morning slip.

Question: they say to check the stick in neutral...in park my stick reads full but in neutral it barely registers on the tip of the stick after 4 quarts...should I fill until it reads full in neutral? The manual said 3.5 quarts and it should be only slightly low.

:thanks:
 
#12 ·
dodgedawg said:
there were metal fragments stuck to it as well as infused in the oil. That magnet in the bottom of the pan, presumably to attract metal fragments was big and fuzzy like a donut with muck and fragments.
Most of the Dodges are like that.


dodgedawg said:
pretty lame given the whole thing took less than an hour and $25. The transmission shop a block from my house wanted $149 for 'service' which turned out to be nothing more than fluid/filter change.
That's the going rate really.

dodgedawg said:
Question: they say to check the stick in neutral...in park my stick reads full but in neutral it barely registers on the tip of the stick after 4 quarts...should I fill until it reads full in neutral? The manual said 3.5 quarts and it should be only slightly low.

:thanks:
You need to be adding fluid. Park means nothing. There is hardly any fluid flow in park. That's why they tell you to check in Neutral.

You'll know when you are too low though. Because it'll feel like it's in neutral when you get in the throttle and then slam into gear.
 
#13 ·
It ended up taking another full quart and wow what a difference that fluid change made. I didn't realize it before (first diesel) but I don't think the TC was locking up at all before. Now it locks up, it seems, when it's supposed to and the power to the wheels is MUCH increased. I truly believe this is why my MPGs went down to 10 but I'll know for sure when I get more fuel run through it in the next few days. The fuel needle did seem to be going down alot slower yesterday and it only makes sense cause it takes alot less throttle to run up and down these hills now. The manual TC locking switch I installed works flawlessly though I plan to use it sparingly. What I really want now is a light that fires when converter is locked.

As for the 'cold morning slips'...they're gone.
 
#15 ·
Thanks, good tip. I did pull drain bolts from an access panel on the transfer case which drained another quart or so. On the stick I can tell there's still a fair amount of dirty fluid in there, is it a good idea to flush it? I saw in one of these threads a guy who pulls a cooler line and runs the tranny in neutral forcing out 2 quarts at a time before replacing and repeating until it comes out bright red; will this work?
 
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