Allison Tranny Wont Shift Into 5th Gear.....

DURAMAXXED · 03-23-2006, 10:33 PM

WELL ABOUT THE LAST MONTH MY TRANNY WONT SHIFT INTO 5TH UNTIL TRUCK IS DRIVEN FOR ABOUT 4-5 MILES. HERES THE SITUATION .I START MY TRUCK UP LET IT RUN FOR ABOUT 10 MIN THEN I TAKE OFF AND IT SHIFTS INTO 1-4 NO PROBLEM WHEN IT COMES TO 5TH GEAR. IT WONT SHIFT INTO IT UNTIL I DRIVEN IT KIDNA FAR RPMS WILL BE 2000 @ 55 MPH AND WILL CLIMB WITH OUT IT SHIFTING. AND YES I KNOW ABOUT THE ALLISON DATA SHEET THAT SAYS WARM UP BEFORE DRIVING AND SHIFTS WILL BE HIGHER RPM RANGE. MY TEMPS HEREIN LAST MONTH WERE NO WERE NEAR 32. TOOK IT TO DEALER 2 WEEKS AGO PTO WAS LEAKING AND I TOLD THEM THEN ABOUT TRANNY IT ONLY HAPENS WHEN TRANNY IS COLD WHEN IT IS WARM NO PROBLEMS. I SAID DRIVE IT FIRST THING IN MORNING. NOPE THEY DROVE IT AFTER I BROUGHT IT THERE AND SAID NO PROBLEMS FOUND ASKED IF IT WAS SITTING BEFORE DRIVEN AND OF COURSE NOT BUT DIDNT KNOW THIS UNTIL IT WAS NEXT DAY . WELL I TOOK IT IN AGAINLAST NIGHT AND I GOT A RENTEL AND I ALSO TOOK THE KEYS TO MY TRUCK AND SAID SEE YA IN THE MORNING YOUR GONNA SEE IT HAPPEN WITH ME IN THE TRUCK. WELL I GOT THERE WE WARMED IT UP AND HE CHECKEDOUT THE LEAK I HAVE COMING FROM THE CONVERTER AREA (NOT BIG LEAK MINOR BUT ACCUALLY MAJOR FOR ONLY 10639 MILESON THE TRUCK) THEN AFTER LETTING IT WARM UP EXTRA TIME THEN NORMAL WE TOOK IT OUT HE DROVE IT AND NOW FINALLY BELEAVES ME HMMMM . HE SAID HE WAS GONNA CALL CHEVROLET AND ASK IF THERE IS EITHER REPORTS OF THIS AND IF HOW TO FIX IT, I TOLD HIM THIS HAS BEEN GOING ON FOR TO LONG EITHER FIX IT RIGHT OR GIVE ME NEW TRANNY OR TRUCK. HE SAID WELL IT IS UPTO GM WELL NOW THE WAIT GAME AT LEAST IM GETTING A CADDY ESCELADE FOR MY FREE RENTAL DAM THERE FUEL HOGS :Peelout

DURAMAXXED

**ob_1jr** · 03-23-2006, 11:39 PM

When is the last time you changed your fuel filter? air filter? tranny filter(s)??Have you ever cleaned your MAF sensor? I would start there.

DURAMAXXED · 03-25-2006, 08:32 AM

well first off i have new air cleaner about 2000 miles ago i did not change fuel filter yet. and tranny filter is coming any day now in the mail! i have 10700 miles on it didnt think i needed to change those other too yet. mechanic went for a drive with me and noticed my problems said yes front seal is leaking and needs to be pulled for front seal ,but he isnt sure what the shifting problem is so he called tech they dont know gee great now they put a computer to my data port and i drive it and hit the button when it wont shift it takes picture of my computer and records before and after i push it and so i did it this morning returned computer to dealer now the waiting game begins.................
thanks duramxxed

BOWTIE2 · 03-25-2006, 12:53 PM

Hey Duramaxxed,

I have always seen this shift situation with my '02. It only shifts to fifth readily in warm weather. If it is 45 outside it takes two, three or more miles to shit to fifth. A couple of times this winter it got down in the upper teens over night and it didn't shift to fifth for six miles. I read that this would be the case, in order for the trans to warm up, not the engine. I found that if I plug in my block heater the night before it will shift sooner but never right away. I always thought this was normal. I am interested to see what they say about yours. I may get some needed work at their expense. Exchanging info like this is a good reason for this forum! Thanks for posting.

DURAMAXXED · 03-26-2006, 05:59 AM

no problem! i never had this problem until about 1 1/2 months ago and here is sc our weathers been mostly in the mid 40's to high 8o's in that time period. i had my truck in Pa. in Jan. where temps were 4 degree lows and had no shifting problems . so my local mechanic thinks it might be some kind shifting actuator that is messing up. but still waiting for final results. will post here soon as possible

duramaxxed

SixInARow · 03-26-2006, 08:23 PM

My powerstroke does the same thing. It's nothing out of the ordinary, most vehicles do that when they are cold to run the engine at higher RPM's to help get the engine warm faster.....

**ob_1jr** · 03-27-2006, 09:50 AM

Quote:

Originally Posted by DURAMAXXED

well first off i have new air cleaner about 2000 miles ago i did not change fuel filter yet. and tranny filter is coming any day now in the mail! i have 10700 miles on it didnt think i needed to change those other too yet. mechanic went for a drive with me and noticed my problems said yes front seal is leaking and needs to be pulled for front seal ,but he isnt sure what the shifting problem is so he called tech they dont know gee great now they put a computer to my data port and i drive it and hit the button when it wont shift it takes picture of my computer and records before and after i push it and so i did it this morning returned computer to dealer now the waiting game begins.................
thanks duramxxed

Sounds like a bad fuel filter. That 15000 miles for a fuel filter change is way too long. I changed mine at 8500 and cut it open...it was pretty black all the way around. All it takes is one bad tank of fuel to mess up a fuel filter.

DURAMAXXED · 03-28-2006, 03:49 PM

thanks ob i will take that into consideration and get me a new one asap... your right about waiting until 15k and one bad tank fuel and your right that all it takes i have seen it my self.now as for the tranny filter when is a good mileage range for that? i dont haul anything with my truck always drive it sensible.

**ob_1jr** · 03-28-2006, 04:48 PM

I believe they say to change the external one every 25,000 miles. I have read that is too long also. I change mine when I change my engine oil. About every 8500-10,000 miles. I figure to just change the filters at the same time that way I don't really have to remember when I did it last. Also, it is cheap insurance on a very expensive investment. Just remember to pull the magnet off the old filter and put it on the new one.

mschn99 · 03-28-2006, 06:31 PM

boy...if at 8500 miles your fuel filters are plugged.....either you are getting TERRIBLE fuel and need to switch fuel stations....or chevy is using a way too small fuel filter. the ford 6.0 is very picky about fuel filters being plugged.....if fuel pressure isnt maintained due to a plugged filter......injector failure is immenant.....and i have never seen one with low pressure or an extrememly clogged filter if they are changed every 15k............you guys have me curious from a mechnanical standpoint now........Marc