jka

Just bought a 2003 dually......have to change my signature.
When driving in the city the transmission almost never makes it to 4th gear and locks the torque converter. Only way it will get to fourth and lockup is on the highway. It has a 3.73 rear end and is 2wd.

Is this normal or should I take it in to the dealer?.....still lots of warranty.

Thanks.

dieselrob

Not shure if it is like the 47re where you can turn o/d off with the button and it will lock up in third. I never drove a 3rd gen auto only handshakers. But i would think they still have the same o/d lock out to get 3rd gear lock up for slow driving.

bigdav160

Dodge's programming of the 48re seems to key in on vehicle speed. Other manufacture's are much more throttle sensitive.

Like clockwork, my truck shifts into OD and locks up the torque converter at 50mph.

06Cummins

yea at 50 it will lock in OD...to me its pretty annoying bc i do like 95% city driving and i never get going that fast...i wish it locked in the 45 range or even 42ish would be nice...my F250 locked at 45 so i would just get it to 45 and back off to 40 with it still locked....but getting up to 50 and locking it would be pushing it..plus it unlocks at 45 again...Jason

abc4yew

Stock the TC locks up at 48mph. I think there are some little white switches under the dash to change your shift points. Do a search on lockup switch by John Rodriguez for a manual switch. I have an ATS transcommander and can lock up my tranny normally as low as18mph or even 9mph if I want. I think I'm going to switch to 9mph for getting heavy loads going out of the hole. Once it locks it makes the truck a rocket ship or a tractor if your in 4lo. Locking early will kill an unmodified tranny. 06's support locking up early as they are exhaust brake compatible. Mileage sucks when you are not locked also. ks

jka

deiselrob.....I've turned off the OD but I haven't noticed if it locked in third.

I'll put that on my "to do" list for tomorrow.

Nuttymopar

My 05 goes into OD at 50 and will lock the TC at that speed also.

I have done the TC lock switch and now can lock at any speed in any gear. Just need to remember it is locked in as it will not downshift while locked and starts clunking pretty bad when coming to a stop when locked. Hit the button and back to normal.

I tapped wire # 7 from the ROUND switch on the tranny and ran that to a 2 pole switch on the dash. Then ran a wire to a 33 ohm resistor and then to ground. Hit the switch, LOCKED tc. Leave the switch disengaged, runs like normal.

Great for around town cruising at 40 mph with it locked in and idling down the road pretty much.

06Cummins

ok, so did you not run a wire from pin 37 to 87? Sorry, wiring is far from my cup of tea. I understand everything up to running the wire to the 2 pole switch...the rest is a blur...lol. Do you have any pics or drawings by anychance? When it comes to wiring that is what i need...thanks, Jason

jka

Read the manual this morning.

Like you guys said the TC will lock at a preprogramed speed in 4th gear as long as the tranny fluid is warmed up. (Fluid must be up to temp. before it will even shift to 4th.) It also leads you to beleive that if you turn off OD it will lock up in 3rd. although it doesn't come right out and say it.
It states it won't lock in 1st. or 2nd. gear.

You would think in a towing situation if you are in OD and the tranny shifts down to 3rd. the TC would lock up.

I haven't figured out yet when city driving with OD on, and the truck is running in 3rd. if the TC is locked. Anybody know?

bigdav160

There's a lot of misinformation and misunderstanding about the purpose of lockup and the function of the torque converter.

The torque converter must lockup in overdrive or the fluid will overheat and loose it's ability to lubricate the transmission. This is especially true in heavy vehicles and while towing.

The lockup clutch lining is rather small. This is because it is intended to use in "low torque" situations (overdrive). The computer won't lock up the clutch unless it thinks the driving conditions are steady throttle and low torque. When driving in "D" range it should lock up the clutch but not right away.

The poeple that are overriding the lockup function are probably accelerating the wear on the lockup clutch plate. The aftermarket torque converters have addressed this issue with larger linings and multiple plates.

jka

Okay....While city driving truck shifts to 4th but the TC doesn't lock up.
Only time the TC locks is when speed reaches 80 kph. and unlocks when speed decreases to about 72 kph.
As far as I can tell TC doesn't lock up in 3rd. gear ever.

Does anyone know if it should lock up in 3rd?

Thanks Again.

Raspy

Mine locks up in Tow/Haul but only under load. Back off on the throttle and it drops out. It also only seems to lock under light load and maybe with lots of on-off throttle (in Tow/Haul).

Wetspirit

N.Johnson

[QUOTE=jka]Okay....While city driving truck shifts to 4th but the TC doesn't lock up.
Only time the TC locks is when speed reaches 80 kph. and unlocks when speed decreases to about 72 kph.
As far as I can tell TC doesn't lock up in 3rd. gear ever.

Does anyone know if it should lock up in 3rd?

Try this on your truck. Mine is a 03 maybe different? Turn the od button off. Drive till it reached 80 klicks and the convertor locks on mine. Very noticeable but not the 400 rpm drop like 4th gear lockup.

bigdav160

[QUOTE=N.Johnson]The shift to OD should be a 30% drop in rpm. Lockup will be another 10%.