It starts like this at 24,000 miles or just over my transmission bottomed out...going down the interstate at 75 miles per hour I lost it. After being towed about 1 1/2 hours to my chevy dealer.. because no dealer was able to get it in the shop for at least a month... they open it up and found missing bearings. Allison without question replaced with a NEW transmission and new warranty. So about 13,000 miles later I am having problems again. when I run 80 (which is normal for Interstate travel) it sounds fine, just near 85 it jerks with me and then it sounds caught between gears. I don't know what could be wrong. Could it just be my timing? I'm terrified i have another FRIDAY PRODUCT transmission when Allison is suppose to be a trusted brand. If I get another transmission they better just give me a new truck for all the headaches and having to drive cavaliers around while they fix my truck! BTW: I baby my truck, no loads, no pulling, no towing.. its totally road miles. I called the dealership today they said to bring it in and "take a look at it" but i would like to hear from anybody else if this is something i should be worrying about or if its easily adjusted???





thanks,


Jess

Jess


Are you sure it isn't the pilot injection coming on and off? Between 82 and 85 mph, my truck does the same thing but it is not the trans.


mike

I'm not sure what that is. I never heard this with my old tranny, then again my old tranny was missing a few parts. I'm sorry that I am so uneducated about my engine but what goes on with the pilot injection??

Jess


It's time for one of our experts to explane pilot injection. " I don doo that kind of vork" ( Arnold S.) http://www.dieselplace.com/forum/smileys/Big Smile.gif


mike

Well i've been advised that my problems could be a series of things. most believe that it is not my pilot injection...


Here's a comment from another duramax owner:


"There is a neutral switch on the trans somewhere. Have heard of tells about the switch shorting out or losing contact at times. If the trans is kicking out of gear this is something that needs to be looked at. As far as the pilot injection kicking out or dropping off, I don't believe that is your problem. Someone needs to take an scan tool and ride with you and watch the input and output voltage signals while the problem is occuring. As far as the air filter. The engine should derate it is for filter restriction. Did anyone notice where the air filter restriction gauge was at when they pulled the filter out. Also watch running the K&N filter for normal everyday use. I know that you are wanting your truck to last you long time. The K&N will flow more air than the stock paper unit, but it will also let more dirt in also. It is not the best thing for dirt "gravel" roads, hay fields, etc. Been there and done that. You would be amazed at what the dirt or silicon levels will do in the oil. "

Jess


Could be as simple as a lose connection on the transmission.NSBU ? Perhaps but I would believe it would give other little fits along the way.


Are you accelerating when the truck jerks? I know it's used as a cure all response but when was the last time the fuel filter was serviced?


I would also luv to know what bearing was missing that showed up causing failure at 24,000 miles later.


Unless the speed limit is 85 legally good luck getting a tech to go for a ride to diagnose. Hopefully you know someone to help you out,if this is the only time and symptoms you have.





Mac

Mac wrote: Unless the speed limit is 85 legally good luck getting a tech to go for a ride to diagnose. Hopefully you know someone to help you out,if this is the only time and symptoms you have.


This is very true. I had a '95 6 speed Z-28 that had acceleration (timing) problems and wouldnt go above 4500 rpm without breaking up. The 2 on duty service managers told my I shouldnt be driving that way, and to keep it under 4500rpm. I had to sit and wait for a 3rd service teck to become available. I was quite upset and showed him (and the managers watching) the problem before ever getting out of the parking lot!http://www.dieselplace.com/forum/smileys/HiHi.gif


Tell them it does it at 70 mph and just run it to 85 after they are in the truck. Just an idea.

My grandfather is the one who got to see the opening of my tranny hands full of shavings fell out and no one could believe that I went 24,000 before losing everything. They had never had such a problem at my dealer with any allison sold since 2001. Mine was the first allison replaced without question. Afraid of suit i suppose. Going as fast as I was when it decided to go out I was lucky i didn't tear up the rearend and possibly worst for me personally. The parts of the tranny had gotten So HOT that they were warped and discolored. No lights on my dash ever indicated a problem.


Believe me when I got off of the interstate you could hear the grinding overtop of the road traffic and my radio..





jess