[dragracer7383]

First let me say that I have not driven my truck enough yet to know it's behaviors all that well. Just bought it a while back. It's a 99.5 dually with an automatic. Has about 88K miles on it. No idea what it was used for before I got it, but it did have a 5th wheel(gooseneck) ball in the bed when I got it. I noticed a couple of times that the transmission didn't act like it wanted to upshift into OD. I first noticed it when I had the cruise on while pulling my new trailer(empty) home. It stayed in 3rd gear until I release the CC and then it shifted up into OD... and was fine after that. There was one other time that I remember it doing something similar. Does this sound like a problem with my tranny, or is it normal for it to stay in 3rd gear sometimes?? /ubbthreads/images/graemlins/confused.gif

 

[haul_n_horses2]

One of the best mods you can do for your tranny is to replace an accumulator valve and some springs in the valve body. goes by the name Sonnax-tricumulator mod. Buy the parts and download the directions for free from www.dieselinnovations.com for $50. Normally, mine will shift from 3rd to OD at about 40 mph on level ground. But mine will hold in 3rd if I am climbing a hill with a load and accelerating even slowly. Stays in 3rd until about 55mph and then shifts up or it will shift up if I back out of the throttle a bit and just maintain my speed up the hill. Shifts are firm and fast with this mod. Perhaps the previous owner did this mod to his tranny. I'll bet he did if he towed anykind of heavy GN trailer.

 

[Larry M]

David,

Since this a new to you vehicle and you don't have a lot of info maybe on the past history some of the first things I would recommend in theontinue

 

[Larry M]

David,

Since this a new to you vehicle and you don't have a lot of info maybe on the past history some of the first things I would recommend in the following order are to change the following fluids (the first three in like the next three mos or 2K miles or before doing any serious towing) and the last three like in the next 6 mos.

1. Engine oil and filter
2. Tranny "flush" using the FAQs here. With that taletale gooseneck ball and if you live where there is a lot of gooseneck towing you might consider putting in one of the $20 inline Magnefine tranny filters after your coolers just as a preventive step.
3. Cooling system drain/flush using the FAQs here.
4. Brake fluid change
5. PS fluid change
6. All the Differentials fluid change

That will give you a baseline and at 88K all six would be a good idea IMO is you're not absolutely positive on what was done and how previously.

You might look thru some of the "little secrets" since you can't search for anything newer than like 7/03 which really hurts, so while not all inclusive at least the "little secrets" do have some more current info readily available even tho they are somewhat limited in scope and by no means all inclusive.


Larry, keeper of the <font color="red"> New revised </font><font color="blue">"little secrets" </font> CLICK HEREhttp://forums.thedieselstop.com/ubb...73329&page=0&view=collapsed&sb=5&o=31&fpart=1 /ubbthreads/images/graemlins/smile.gif

 

[dragracer7383]

OK thanks guys. I was planning on the engine oil change soon follwed by the trans flush soon after that. I will probably also go ahead and do the other stuff you recommended and also replace the fuel filter just so I know it's not a possible problem area. This is the first diesel of any kind I have ever owned so I'm not all that familiar on what needs to be checked and how often. Been doing lots of reading and trying to get myslef up to speed om this stuff before I start asking a lot of dumb questions. Just thought the shifting deal was a littl wierd. Thanks again.

 

[4cstr]

Dragracer...with the shifting into OD thing. Does this happen. You are cruising along...with cruise on...and head up a hill. The tranny downshifts to hold cruise. You top the hill, but it won't shift back up to OD unless you toggle the Tow On/Off button...or something similar.

If that is the case...it may be programming in the PCM. In my early 99 when I had the XLE4 programming...it would do that. It wouldn't shift back into OD when the cruise was engaged. I had it flashed to XLE8 and the problem went away.

It might just be as simple as that.

Dave

 

[miteyvictor]

It turns out that this is a common problem.
When I scale a long hill in 3rd and the crest is a very gradual change, the tranny wants to stay in 3rd, even when you are heading down the other side!
For now, I'm tapping the brake, then hitting resume.
Next time I visit the dealer, I'll reflash.
/ubbthreads/images/graemlins/smokin.gif

 

[dragracer7383]

[ QUOTE ]
Dragracer...with the shifting into OD thing. Does this happen. You are cruising along...with cruise on...and head up a hill. The tranny downshifts to hold cruise. You top the hill, but it won't shift back up to OD unless you toggle the Tow On/Off button...or something similar.

If that is the case...it may be programming in the PCM. In my early 99 when I had the XLE4 programming...it would do that. It wouldn't shift back into OD when the cruise was engaged. I had it flashed to XLE8 and the problem went away.

It might just be as simple as that.

Dave

[/ QUOTE ]

Dave that sound exactly like what it is doing. Won't shift back into OD until I kill the cruise. After It shifts back up to OD I can go right back to cruise control with no other problems. How do I go about getting this "XLE8" flash?? /ubbthreads/images/graemlins/shrug.gif

 

[dragracer7383]

[ QUOTE ]
It turns out that this is a common problem.
When I scale a long hill in 3rd and the crest is a very gradual change, the tranny wants to stay in 3rd, even when you are heading down the other side!
For now, I'm tapping the brake, then hitting resume.
Next time I visit the dealer, I'll reflash.
/ubbthreads/images/graemlins/smokin.gif

[/ QUOTE ]

Yep, yep, yep........EXACTLY what I have been doing. This has got to be more than a coincidence. /ubbthreads/images/graemlins/bleh.gif