I just bought my '90 W250 replacement last weekend. It's the first 3/4 ton truck I've ever driven that has had an auto transmission, so despite the convenience of not having to row through gears, it is a bit different for me.

I changed the filter and oil, and adjusted the bands, on Saturday, and found more material in the pan than I'd like to see. Since the change, I've put over 700 miles on the truck, so I'll likely change the oil another time very soon. I'm trying to get it all flushed out.

I only have one question right now, but will more than likely have several more in the future, so I will return to this thread when those questions pop up.

1) The shift from 2nd to 3rd seems to take more than time than what I perceive as necessary. The engine revs just slightly, and after no more than one second, it shifts to 3rd. This is when accelerating slowly. Is this correct? It acted the same before and after the band adjustment.

I'm thinking my best bet would be to have somebody, who also has a 47RE tranny in their Dodge, ride in the truck with me and tell me if everything seems correct. Anybody nearby?

 

2) How much drag is the TC supposed to have at idle? The following has happened to me twice. I start up the truck, put the transmission in Reverse, add slight throttle to back out of a driveway, release the throttle, the engine slows and dies. It then seems to take a bit longer to start then it normally does.

 

What is the idle speed set at? Should around 850 RPMs, in drive, with the A/C on. Easy to change.

http://www.dodgeram.org/tech/dsl/adj...d_Gen-Idle.htm

 

I don't have an actual test tachometer, but in Neutral or Park with the AC off, the needle is just above (one needle width) the first line below 1000 RPM on the gauge cluster tachometer. When in Drive and with the AC on, the needle is just below (one needle width) the line. It "sounds" just about right.

 

More questions/observations

3) The transmission seems to shift very softly, to the point that you think it is slipping. If I just put it in Drive and accelerate normally (not slow but not fast), the engine just kind of stays at the same RPM. It does vary slightly when the transmission shifts, but not by much. Then when the TC locks up, the engine drops by at least 500 RPM (I'll have to get an exact amount the this afternoon). However, if I start out in 1st, then manually shift to 2nd, and then on to Drive, I can feel it shift firmly. If the transmission were in fact slipping, wouldn't it also do so when manually shifting gears? Why doesn't it shift firmly when starting out in Drive?

2) More on the engine dying in Reverse. It happened last night when backing into my driveway. It is slightly up hill, so I would put in Reverse, give it fuel, then step on the brakes. The engine would slow and die. It didn't seem as if the TC was grabbing too hard and killing the engine, because I would assume the truck would shake just like it would with a manual transmission and you came to a stop without depressing the clutch. Any ideas?

 

Royta, mine dies like yours when the engine is cold and I have read that it could need the timming set (hopping to do soon anyway) or the idle may be to low. Try searching these 2 things it may help, or some of the pros may jump in. just my .002

ps congrats on that new rig

 

Rota, your idle rpm in drive with the air conditioning on is 700 rpm, one needle width below the hash mark. It is supposed to be 850 rpm, two needle widths above the hash mark.

It might sound about right but will have a problem and die when shifted into gear. Been there, done that.

 

i would personally add a little throttle pressure with the kickdown linkage to see if it will help. mine is not an e model but it works the same. i have mine past the adjust and added a bolt to give it 3/8s in. more with no problems for over 4 years. if it stays in a gear too long after adjustment just back of a little at a time til you get what you want.

 

I think my problem is a high stall TC. I've done a bit of searching the last day or two, and my symptoms (revving to 2500 RPM, the truck catching up, and dropping 100 or so RPM's when shifting) seem to indicate a high stall TC. It makes the power felt between a manual transmission and an auto a night and day difference. Kind of depressing actually.

 

As far as the engine staying at the same rpm while the truck accelerates, that is normal. Mine did it 'til I invested in a good tranny. Used to be I would set the tach on 2000 rpm and wait for the truck to catch up. Now I don't even have to go over 1600 rpm and I get up to speed faster. If you have any questions just go to the links page and look for a phone number for any of the "big 4".They will all be able to help you.
Tom

 

Thanks MnTom. The more I search and read, the more I think that my transmission is acting normally. Plus, the more city driving time I put behind the wheel of this truck, the more I understand what is going on in that old slushbox. However, it is certainly necessary to apply the brakes when the transmission is in gear, as the TC will certainly grab at idle.

The only problem I have now is when the engine dies when giving a small amount of fuel in reverse, then stepping on the brake. Sort of like what you do when you want to back up a hill about a foot or two. The engine will just die on me. I'm going to bump the idle speed just a bit sometime this week.