automatic transmission late shift

[Sam53]

Hello every one.

I'm new to this sit and have a 2000 quad cab 2500 4x4 8ft bed, 24v cummins whit automatic transmission I thing it's 4 shifter (sorry i'm new whit this kind of transmission)** & all stock except lift pump which is last week went out and I change it to DRRP02 FASS 110 GPH,other than that untouched truck, anyway, I've to get the RPM over 2k or 22k till shift to the upper and only on the highway goes to 4th and O/D otherwise just only 2 shift. is it normal? I fell engine is under the presser and need the another gear or shift so. In the city with 1500 or 1800 RPM still stays on 2nd shift at 40 to 45 MPH I think is something wrong with it by the way is there any way we can add the one more shift to transmission or not? is any 5 shifter or more is available in the market so we can replace it with this 4 shifter? how much is cost? I knew it maybe the same topic from the other members but I really need your expertise HELP and I need to know what to do as much as I can by myself cause I'm on the very tight budget.

Appreciate for your help.

PS** I'm a semi tractor trailer driver and use to change gears (18-15-13 speed / straghit 10 or supper 10 speed gear box) even my 2000 Honda Accord is 5 speed manual and auto trans is little bit strange for me sorry I don't want to be selfish just want you know my fillings abut the situation.)                   

Edited March 15, 2016 by Sam53

[Me78569]

In city driving I would expect to see 1-2 shift 10-15 mph, 2-3 25-30 mph, 3-4 shift ~45 mph.

 

You should look at the adjustment on your TV cable.  It runs from the APP / TPS sensor on the engine down to the tranny.  The tension / throw on this cable is what controls your shift points.  tighter tv cable = holds gears longer

[Sam53]

thank you so much for your help and respond.if I go under the truck which side of engine and tranny I need to look? do we have any measurement for TV cable? how do I adjusted it? I would be appreciated for Knowledge and expertise.  

[notlimah]

I know you said the truck was completely stock but does that mean stock tired as well? Just curious because my two trucks shift at different points with different sized tires 

[Sam53]

my truck comes with 35" alloyed aluminium wheel form factory.

[notlimah]

Ok well if you're running 35's that's going to have faster shift speeds. It still seems like yours is running a little high though. Mine with 35's will typically shift from 2-3rd at about 35-40mph but probably around 1500rpm. Just trying to give you something to go off here. What Me78569 said is what you want to check though. Just figured if you have nothing to go off you could end up all over the place. Hope this helps! 

[Me78569]

Yea I think your issues are in the 35" tires mostly.   I dont know if you meant that the 35" tall tires are factory or just the rims, but your issue can be explained in 2 ways.

 

1. you tires are almost 5" taller than factory so your truck thinks you are going slower than you actually are, thus it will shift at high speeds.

2. the 35" tires are much heavier and much harder to turn due to increased rotational mass and a longer leverage arm.   so you are having to use more throttle input that most of us when accelerating.  This means that the TV  cable, again driven off the Throttle, is pulled more.   That a lone is going to raise your shift points.  

 

If you 3.55 gears on your truck you effectively make them 3.05's by running 35"s tall tires.  

 

Now you can adjust your TV cable for more slack to help with the issue, but I don't know if I would do that.   Not only are you decreasing shift speeds, but you are also lowering tranny pressure at a given throttle position, IE less holding power. 

[Sam53]

Thank You guys Now I get the picture what's happening. I've same shifting as notlimahs truck dose but @ 2000rpm and Me78569 you are right I'm not going to touch TV cable and create more problem. by the way today I try to find the TV cable on my truck but I couldn't!!! maybe it's just me or my electric throttle. I don't know some advise would be help. 

Thank You and these information are very helpful.     

Edited March 16, 2016 by Sam53

[Me78569]

The TV cable is under the black plastic cover on the front drivers side of the engine.  There is a cable that runs down to where your shifter linkage attaches to the tranny.  

 

One arm is for the shift select the other is the TV cable.

 

use the Mopar1973man part number lookup tool

Page: 472 part #23

https://mopar1973man.com/external-media/pdf/2000Ramparts.pdf#view=FitB&page=472

 

 

Edited March 16, 2016 by Me78569

[Sam53]

Thanks for the help. 

[Sam53]

Hello again

Today I keep tracking my RPM & speed again to make sure transmission  just doing fine. from 0 to 25 @ 1st shift with 1700 rpm than changed to 2nd,  with 2nd & 2200 rpm speed does till 50 then all of the sudden change the shift to 3rd Immediately 4th or O/D and speed don't ask 120 mph with 2500 RPM.  I'm not happy with it. make me worried abut engine. getting high RPM till shifting is not good for the life of engine ad trany,.in the other hand going up the hill with just 2 or 2.5 degree and empty 2200 RPM only 2nd shift 25 top 30 mph !!! how abut polling the loaded trailer or RV in the pass between Idaho & Montana or Eisenhower pass on I-70 Colorado,  then how may or how much engine must be going under presser till rich the summit? is she gonna blow up? 

Please Pleas please help me for this nightmare

THANK YOU 

[Mopar1973Man]

It's just not efficient. As for RPM causing harm, these engines take a beating towing. Like my trip to @Dynamic shop several grades I was holding 2,200 to 2,500 RPM towing 8,000 pound RV. The tires are your biggest problem. Just for fun if you can find a friend with stock 31" tires swap with him for an afternoon and see if the transmission works better. Cost nothing but time to swap tires.

[Me78569]

Try some stock sized tires.   Has the truck always been like this?

 

The 1st gear shift rpm is about right, but due to the tire size it is ~25 mph vs 235/85/16 ~18mph

2nd to 2200 rpm really isn't that far off either, assuming you are at ~30%-%50 tps or so.  I would image you would be since you are having to spin the big tires with 3.55 gears.

3rd I don't understand what you said happens, can you explain in better detail?

4th same don't understand.

 

You might change your OSS on the trans just to see if 3rd and 4th act better, but unless you regear or get smaller tires I think you will be unhappy.  I wouldn't worry about the engine 

 

Remember your MPH is WAY off with those tires also.

[Dynamic]

Yes, we need more information...

At moderate throttle, I like to see both the 1-2 and 2-3 shifts at about 2000 rpm. They should both be pretty equal as long as your throttle setting doesn't change. Your TCC lockup and 3-4 shift are simply commands from the PCM, so their shift points are going to be determined electronically and the TV cable has nothing to do with them, other than determining the amount of line pressure at the time of their commanded engagement.

A good starting point for TV cable adjustment is to set it so that the end of the cable is exactly lined up with the ball on the lever arm at the transmission. Make sure that the spring is in place and the arm is all the way forward.

[Mopar1973Man]

At least FSM shows that throttle and TV arm should move at the same time. Starting from fully forward on the TV arm.

[notlimah]

Is the sudden shift you mention from 2nd @ 55mph and suddenly to 3rd or 4th just it locking the TC in 3rd? Mine will do the same thing, although even with 315 tires I'm seeing 2000rpm and 50ish mph in 3rd with no lock up. Then 3rd will lock until around 60 then shift to 4th then 'OD'

[NightHawk]

I have 285/75/16 tires on my truck with the 3.55 gear set and a stock trans (don't know 100% but pretty sure)

After spending several hours in total making minor tweaks to the TV cable, I finally got my trans to "hold" gears regardless of throttle position (aka a min mph up-shift speed).  Does this sound "normal" to the group, as its great to drive around with an auto & have some engine braking.

My Trans shifting at a low tps (10-20%):

• 1-2 shift at min 10mph per my speedo, if using low input of throttle and let off below 10mph it will not upshfit
• 2-3 shift at min 20mph per my speedo, if using low input of throttle and let off below 20mph it will not upshfit
• TC lockup will occur 30mph to 35 mph with od on/off (only if already in 3rd gear)
• 3-4 shift a min of 45 mph but unlike 1, 2 & 3 will upshift from 3rd if button is off & i lift below 45mph
• 3-4 shift with OD button off (light) will shift with the TC locked when turned on (if above 45mph)
• 3-4 shift with OD button on (no light) will unlock TC, shift and then re-lock the TC instantly (above 45mph)

 

Edited March 19, 2016 by NightHawk

[Sam53]

I'm appreciate of all of you guys for responding to this topic & sorry for being late on get you back some up date.

in the attachment you can see the picture of friend of mine tire size & rem that I barrow for test the trany again.         it dose the same thing (1-2 /rpm 1700 / 20-25 mph). even lock on 2nd till 2200 rpm / 40-50 mph then shift to 3rd. as soon as it shift to 3rd I mean by the Second shift to 4th  (3-4 rpm 2200). @ 2000 rpm speedometer shows 65 mph and that's it, no more shifting (O/D light off). with O/D light ON stick on 3rd - 2200 rpm & speed up till 55. 

I wish I could explain more or find the other way to do it please forgive me. 

[Buzzinhalfdozen]

Could you take a video of the speedometer while you're accelerating? 

[Sam53]

Thakns for respond I try, but it's a little bit hard and difficult.