Hey all! my allison 1000 will not shift from 2nd to 3rd when you get on it from a dead stop. you have to let off the throttle to get her to shift and then its fine thru the rest of the gears. It worries me because it gets right up on the rev limiter and just doesnt sound good. Dont get on it like that right now but thought i would ask if anyone has any insight as to the cause. Would a good tranny service and adjustment straighten it out? How often should the tranny filter be changed?

When was the last time you changed your engine fuel filter? A restrictive fuel filter can cause these symptoms.

Fuel filter.

Check the fuel filter as stated its a lack of power causing the issue

Check the fuel filter as stated its a lack of power causing the issue


x2 and no codes??

xwhatever on fuel filter

I am having this exact same problem today. Delayed shift and not much power from 2 - 3. Last changed the fuel filter 10,000 miles back. I suppose I'm due. No CEL and no codes.

You're due, but it should give you a P1093 code.

Almost always the fuel filter. Miles driven are only a vague indicator of filter loading status. Fuel quality/economy have a big impact. There's an easy to take the guess work out:



http://www.kennedydiesel.com/images/Dmax-fuel-filter-rest1.gif

I had the same problem once and found that the drain valve at the bottom of the fuel filter was leaking. This was allowing air into the system and not allowing optimum fuel pressure at WOT. Tried tightening the valve but it continued to leak. Replaced the valve and the problem was fixed. Take a look at yours and check that this is not the prob. good luck .. hope you get it figured out.

Ok - on the way home from work - I was driving her hard. Then it felt like I limped the Duramax. Wouldn't go over 65 and absolutely no power. Plugged in my Predator and had a P1093 code. Picked up a fuel filter and holy SH!T, what a difference. Problem solved. I just can't believe I didn't notice the power loss up till now. Thanks guys for the help. Sucks changing the fuel filter out in 10 degF weather. Hands are quite pissed!!!!

My truck was doing the same thing and I took it to the dealer and they replaced the fuel filter because it was pugged

i have this same problem.... i figured it was my tranny because i got a 5" exhaust and a quadzilla stealth 2 set @ 135 which is quite a bit for a stock tranny. if i give it WOT off the line it does good than from 2nd to 3rd i have to let off, let it shift and give it again and it goes. could that be the fuel filter also?

Quite honestly, it's a quick and rather cheap thing to try. Can't go wrong with changing your fuel filter and go from there. Like others stated above, start with the fuel filter, then try the spin-on Allison filter, after that, it may be that you simply don't have enough fuel pressure running a 135hp tune. May need a lift pump to keep the fuel pressure up.

how hard are the fuel-filters to change. this is my first diesel and the first oil change and all that i took it to the stealership cuz they gave me a free oil change when i got the truck. had em change the fuel filter also

i have this same problem.... i figured it was my tranny because i got a 5" exhaust and a quadzilla stealth 2 set @ 135 which is quite a bit for a stock tranny. if i give it WOT off the line it does good than from 2nd to 3rd i have to let off, let it shift and give it again and it goes. could that be the fuel filter also?Im 99% sure the quads defuel during shifts.

how hard are the fuel-filters to change. this is my first diesel and the first oil change and all that i took it to the stealership cuz they gave me a free oil change when i got the truck. had em change the fuel filter also
Screw the dealer, do it yourself to make sure you know it gets done right.

As for the fuel filter, i take my time, take off inner fenderwell liner and its right there to get at with a oil filter wrench. You then need to transfer the WIF(water in fuel) sensor (at the bottom of the filter) to the new filter, and re-plug in the sensor. Be careful when you transfer the new WIF sensor to the new filter, you can round off the plastic on it. Prime the filter by pressing down as much as you can on the pludger, for me about 25/30 times. start truck and let it idle, if it dies, repeat last step.


Ohh btw, check your rear end diff level. 5 bucks says its a quart low.

thanks for the help i appreciate it. but i dont think its a defueling thing. cuz it wont shift at all i have to let off a lot for it to shift

i have this same problem.... i figured it was my tranny because i got a 5" exhaust and a quadzilla stealth 2 set @ 135 which is quite a bit for a stock tranny. if i give it WOT off the line it does good than from 2nd to 3rd i have to let off, let it shift and give it again and it goes. could that be the fuel filter also?

Yes most likely that is the fuel filter causing your shift to hang at WOT.

alrighty thanks guys i hope thats all it is

changed the fuel filter and now she shifts like a champ...... but now i'm getting an engine light does anyone know where i can get codes checked free in san diego, ca???

changed the fuel filter and now she shifts like a champ...... but now i'm getting an engine light does anyone know where i can get codes checked free in san diego, ca???


I don't know your area for sure but Autozone and Advance Auto will usually check codes.

changed the fuel filter and now she shifts like a champ...... but now i'm getting an engine light does anyone know where i can get codes checked free in san diego, ca???

If you have an AutoZone nearby, they do it for free.