48re trans with delayed overdrive shift at %50 throtle

[GregTaylor]

I was reading this TSB on 47re trannies and they mentioned that the transmission will delay the last shift before overdrive until the truck reaches 70 mph. with the diesel pedal depressed %50 then it would shift in to overdrive. they said the transmission needs a software update. well according to my sales receipt i have the 48re tranz. but i have noticed the same problem unless i completely lift off the diesel pedal at 60 the transmission won't shift until it red lines at 70 then it shifts. not to mention if I'm accelerating reasonably at 50 the od kicks in with a massive clunk and throws my head back. anyone else have a similar problem



the tsb is

http://dodgeram.info/tsb/2003/18-015-03.htm

 

[catoiler]

Yep mine does the same thing 48re,going in to the dealer next week for some minor fixes. Also have the throttle not want to work sometimes after droping into gear, up to neutral and back to drive and it works fine. Other than that this truck is hands down 200% better than my 02 was. brakes are GREAT!on the 02 wasn't sure if you were going to stop or not sometimes!Gotta admit I do miss the power of the 02 with all the mods!

 

[SKelly]

My 48re does the same thing. Pretty annoying. Let me know what the dealer says.

 

[Singletrack]

hard shift into overdrive

Yep, My '03 48RE transmission shifts hard into overdrive. The positive shift doesn't bother me so much. However, I get a strange drivetrain sound when it happens. When it locks up in overdrive, There is a 'hit', knock/clatter in the drivetrain. It doesn't sound right. Does anyone with the 48RE experience the same sound?



Tom



'03 Quad, 3500 SLT Laramie, Sport Pkg, DRW, 4x4, HO/48RE, 3. 73 w/Limited Slip, B&W Gooseneck hitch/tow Pkg

 

[SKelly]

I have the same noise although once in a while. It will shift into OD and I will get a buzz vibration type noise. Are any others experiencing this?

 

[Steve M]

I got the same noise with my 47RE when it was new. When I removed the silencer ring, it quit making the noise. I read that it was the turbo huffing with the sudden rpm drop so maybe the silencer ring has something to do with it. Or it could be total coincidence. I've been giving it more throttle lately to hold 3rd longer. Speaking of which, it's good to see a TSB about the delayed O/D with 1/2 to full throttle. Now we need a TSB (reflash) for the O/D too soon at light to 1/2 throttle.

My '01. 5 wouldn't go into O/D with 1/4 to full throttle until I let off the throttle or hit 65mph. This was great for towing. I rarely used the O/D off button. It did it all on it's own. I got used to letting up on the throttle when I was ready for O/D as low as 40mph. I really liked the program in the '01. 5. It was like full time tow mode. Even running empty was better as sometimes I have to ease up to 40~mph and then pour on the coal to get on the interstate. It never fell into O/D just as I needed power. But people complained and a TSB was issued to "fix" this problem. If I could have my '03 programmed to shift exactly like my '01. 5 did, I'd be so happy I couldn't hardly stand it!

 

[LnRDover]

I have also experienced the quick acceleration at around 50 mph when the OD kicks in. Other than that, my transmission seems to be working fine

 

[GregTaylor]

Originally posted by LnRDover

I have also experienced the quick acceleration at around 50 mph when the OD kicks in. Other than that, my transmission seems to be working fine

say try this next time you merge on the freeway hold the throttle to the floor, when does your truck shift in to od. mine does it at 68 mph just before the engine redlines

greg

 

[MSilva]

48RE

I also have quick acceleration when going into overdrive.

 

[Steve M]

Update on the noise. It just dawned on me. I moved my transmission dip-stick over a tad because it was rubbing on the a/c line going into the firewall at the same time I removed the silencer ring. I put the silencer ring in and the noise is still gone. It had to be the dipstick tube rattling against the a/c line when it locked up in O/D. It wore a little into the line but not bad enough to have it replaced. You can simply push the dipstick tube away from the a/c line and it'll stay.

 

[Tony T.]

I to have experienced this, I guess a clunk noise or almost feels like a momentarily slippage, I don't know. Hard for me to put into words just have to experience it. I have the 47RE. I had talked to Steve M before about this in a different thread. Unless I keep my foot into it, I get this clunk,and quick jerk like, you missed a gear and suddenly realized you did and corrected it, that is a (example) if you were using a stick trans. Been usually pressing the od button around town, but sometimes I'll run up on another vehicle too quick (like a BLUE HAIR) and you dart over to next lane and take off and momentarily clunk, clunk noise happens, or forget to turn off od pulling uphill grade, like left turn going over a overpass clunk,clunk- shift that happened to me just last night. Very annoying, sure needs to hold third longer. It's hard sometimes to roll on it, to keep it from clunking and running up someone's south end. :--)

 

[Steve M]

That's a different noise. I've heard that on any auto I've owned. It's the same noise as when you let off the throttle with a standard. Mine does it when I let off the throttle for the blue hairs just like you say. There's just enough play in the driveline to make it clunk when it's dragging in one gear but suddenly pulling slightly in the next. I don't think it's a problem.

 

[Tony T.]

Happy to here that's not a problem. Still annoying though!