Transmission question

[shorty]

I just traded my 59K mile 10 for one that only has 15k. The looks, ride and overall truck tells me that the 1st one was really abused. The “newâ€￾ one must have been pampered and garaged as the paint is excellent and the rest of the truck seems at this time to be in very good condition. The question I have concerns the transmission. The 1st truck shifted hard, very hard and I attributed that to the diesel transmission. At times I would get on the gas and it would double shift to a lower gear, kinda like it hadn’t figured out which gear was appropriate for the speed and RPM. Well, my “newâ€￾ truck shifts almost like a car in that you can barely feel the shift----that is when you are not floor boarding it. When using a heavy foot it still shifts smoothly, no slamming into gear as the 1swt truck, yet still getting 2nd gear rubber. This “newâ€￾ one is only the 3rd SRT-10 I have been in so not sure which transmission is ok and which is not. Any help would be appreciated. Getting ready to do some small mods and don’t want the transmission failing. Thanks in advance.

 

[TheMoparConnection]

Did the first one have a tune? There's a big difference between one with a tune and one without

 

[NSDQ]

The "hunting" for which gear to be in is a common issue with the 48RE tranny. Upgrading to a GM governor pressure solenoid kit, which can be had via Ebay for $219, generally solves this problem. Many threads on here relating to this topic. So likely your first one was the one with "issues".

 

[shorty]

Do not believe either had a tune. Don't find any information about either one but both had the stock Pirelli tires, no intake mod, no exaust mod so I am assuming neither had a tune. Is the 48RE the tranny that came in my '05 QC?

 

[NSDQ]

Yes, the quad cabs use the same 48RE tranny as in the Cummins Rams, with a couple of slight differences IIRC, but overall, same tranny.

 

[shorty]

Thanks for the info. Assuming both trucks had no tune does that mean that the great difference in shifting has to do with wear, the way they were driven or just individuality? The "new" truck shifts so smoothly that one hardly notices a gear change at “normal” everyday acceleration.

 

[NSDQ]

Yes, wear is ultimately the difference along with maintenance.

 

[shorty]

thanks my man, just got is with 15K so will go ahead and service the transmission. Any recomendations on what fluid to go back with?
thanks again Jason.

 

[SlvrSnake]

The first truck probably had a shift kit installed into the valve body or an aftermarket rebuilt one. If it shifted hard and quick under light throttle that was most likely the case. The stock valve body will shift smooth which in some cases will lead to premature clutch wear if you keep your foot in it because it basically slides into gear which is the smoothness your are feeling. With over 500 ft/lbs or torque and shifting WOT around 6K rpm is not a good combination to be sliding into gear. That is why the stock tune has TQ management which will pull tons of timing out of the truck under WOT to try and protect the trans.

That is why the governor solenoids get clogged up because there is clutch material floating around in the transmision. If the truck you have now shifts good under WOT and is consistent, leave it alone. There are good ones out there that work so if it aint broke don't fix it. Hope this helps.

Use ATF-4 for the trans.

 

[NSDQ]

I just use factory fluid. My tranny has over 120k miles on it and is still working.

 

[VENOMOUS1 RACING]

Yup sounds like the 1st truck had a shift kit as said. The description of your newer truck sounds correct. Now, I do recommend a torque converter and shift kit for this tranny if you plan to keep it an auto
A tranny that shifts quicker will be better on the clutches longevity by a more direct, prompt engagement, versus say a Old Cadillac or Lincoln that you could barely even notice the gear changes. Their trannys also never lasted well!
The 48re was indeed designed for a Diesel Engine that spins to 3500 on occasion but spends most if it's time around 2-2500. Our trannys see 6000 rpm and rotating the heavily designed internal gearing and parts at 6000 RPMs many times just eats this tranny alive!!
Again it was a SRT afterthought to even drop the Vipee engine in a Quad Cab and be a the only Viper with an Auto! They used what they had that would take the punishment hopefully through warranty
A Turbo 400, 4l80E, and other Autos are far more efficient and can hold the power easily.
As for a Daily Driver, I would do the shift kit, converter, and a few other choice modifications and enjoy as long as she'll hold out.
Band adjustment and preventative maintenance are key to any transmissions longevity though so that must be kept up!
:burnout:

 

[Yellow venom]

Like the others have said. If your tranny is shifting real nice and smooth that is wearing out the clutches, cause they are slipping to alow a smooth shift, when they shift real firm that is because the line pressure is increased with a valve body which is the better way to go, a shift kit helps a bit but a band-aid cure in my opinion, the increase in line pressure prevents clutch slippage which cuts down in wear on the clutches, I have my valve body changed and most of my internals upgraded and my tranny is holding up perfectly with a supercharged engine, it gets driven and no clutch stink in the oil or colour change since I put it in 3 yrs ago, HTS Transmissions did a great job in letting me know what needed for it to hold up to the power I'm pushing through it.

 

[spydertt]

As others have said, band adjustment is critical. I've heard rumors they were loose from the factory. If your doing performance mods a shift kit will extend the trans life. I think its Borg Warner that makes an updated direct fit governor solenoid that's cheaper than the GM conversion and has a larger screen,also wouldn't hurt to replace pressure sensor.