02 Duramax..loading up then wont shift...

cgmacd3 · 07-30-2006, 09:30 AM

Hi,

I have an 02 Chevy Duramax with 81K on it, K and N, and an inline predator module. The truck started acting funny and when you step on it it will redline and then not shift...then start to feel like its loading up and kind of bog??? If you baby it and barely gas it its fine........if you put it in neutral and gas it, the motor feels clean and strong. Im def not a diesel mechanic but my first thought is copmputer...but Im not getting any messages or errors. Thanks for any input. Maybe tranny?

Chris

**ob_1jr** · 07-30-2006, 11:54 AM

try changing the fuel filter. Sounds like it is clogged......I know, how does this connect together??? It has fixed many problems like this in the past. Also, you may want to take some contact cleaner or alcohol and gently clean your MAF sensor if the fuel filter doesn't fix the problem.

cgmacd3 · 07-30-2006, 12:13 PM

I just cleaned my airfilter, sorry man, which one is the maf sensor? I had the fuel filter changed about 15k ago??

Thanks

Chris

**ob_1jr** · 07-30-2006, 12:17 PM

The MAF sensor (mass air flow) is just into the intake tube. You need a special bit to take it out if you have the stock intake. Also, 15,000 miles on a fuel filter is way too long even though that's what GM recommends to change it at. I change mine at every oil change (about 8500 miles) and it is pretty dirty. I don't have to change it so often now since I put a Racor 2 micron pre-oem filter system.

cgmacd3 · 07-30-2006, 08:03 PM

How hard is it to change a fuel filter?
Could my tranny be slipping...It seemes like it is fine for take off, but only when i really get on it at speed, then the mortor redlines and then wont shift??

**ob_1jr** · 07-30-2006, 11:26 PM

it is pretty simple to change. check this thread out on another forum....your other option would be to go through the fenderwell. I would also add that once you start to get the filter loose by hand, put a plastic bag over the filter so you don't spill diesel all over when you are trying to get the filter out of the engine compartment.

http://www.dieselplace.com/forum/showthread.php?t=1508

As far as tranny slipping, I wouldn't really think that would be a problem, if it was, you wouldn't be able to pull over 2000 rpms. Have you changed your external tranny filter since you have had your truck??? That needs to be changed pretty often too, But I would start out with the fuel filter.

cgmacd3 · 07-31-2006, 01:26 PM

ob_1jr's ,

I am shocked that it was that frickin easy. I got all the stuff including the cool filter wrench and changed it in less than half an hour. Thank you very much for all the help. Yesterday I was winning like a little b/(&( that my truck was dieing. My filter was a mess, it probably had something to do with running it out of diesel 3 times in the last year! The thing halls ass again. How hard is it to change the tranny thing? I drive my truck and haul toys down to Baja, we have a big trip coming up so I would like to take care of her before we hammer it. Thanks again for the great advice.

Chris

**ob_1jr** · 07-31-2006, 01:31 PM

Glad to of been help...changing the tranny filter is just like changing an oil filter. Just go buy an allison spin-on(red one). I have to use a strap wrench to get it off since it is smaller than most filters (about the size of a motorcycle filter). If your tranny fluid level is in good condition and full, you don't have to prefill the filter or add any to the tranny. The fluid loss is minimal. Just make sure to take the filter magnet off the old filter (looks like a disc). I would recommend installing it on the filter housing and not the filter. It is easier to keep it getting off center.