Auto trans freakazoid or normal?

[JoelAbq]

I was wondering if I had a freak of a truck, someone did some work before me on the auto, or who knows?



When I slide my stock plate slightly forward it still had the break off screw, and as far as I believe the transmission is stock (feels loose when not locked, and the stall is around 2100RPM). I towed a 5000lb trailer around no issues – some hills I would slow down on, but I never thought the performance was up to par with what I am towing now. I bought a Wildcat 27BHWB, real length being close to 30ft and the dry weight is in at 7500lbs. I picked it up 800miles away in Austin, TX and had no issues driving it back at all.



Now we just went on our first real camping trip, and we went to Durango, CO and pulled some of the hills past there. None of the HUGE passes, but right after Durango on US550, there is a 3-5mile stretch of 6-7% grades. I was shocked to find out that when the rest of my family got there that there lighter trailer being pulled by an 8. 1/Allison combo was sustaining about the same MPH as I was. I was down in 2nd gear, 35mph, the Chevy towing a 6500 UVW trailer was doing the same MPH on that hill (no idea which gear?). Overall, am I pleased with the performance! Most of the time in rolling hills, Overdrive @ 65mph does pretty well… and I’ve got the 3. 54 gears.



My trans temps never went over 220, and outside ambient was 95F. I moderated my throttle, I had plenty of fuel peddle left, but more fuel peddle meant I was dumping heat in (previous experience on hills tells me this, I didn’t bother trying on this hill). EGTs were good. I know I can get the heat really cooking the trans if I want to, but I seem to be able to control the heat with the accelerator peddle.



So when people toast the stock trans due to heat, is that because they are stomping the fuel when not locked, or am I missing part of the story? Reason I ask is I want to prolong the stock auto until next season when I have all my pennies saved up. I would like to add a fuel plate after the transmission is replaced, but I am still pretty happy with the close-to-stock combo. Most people I’ve talked to (including myself) are impressed at what this 6cyl can do!



Joel

 

[MEby]

I am not an expert but I think the autos greatest enemy is heat. I'm not sure at what temp you should stay under seeing i've not driven many autos mostly manuals. not having the torque converter locked will cause much more friction and therfore more heat.

 

[tgrfan2]

Your stock transmission is not going to lock in second gear and unlocked it will build heat fast. Yes you will shorten the life of the fluid and your transmission. My suggestion would be to get a plate and 3K GSK. Then prepare for a transmission upgrade. Many like the #10 with the GSK. I like the #6(more torque) but installed it before I did the #3K GSK.
If you can get enough power to stay locked in drive or OD WITHOUT slipping your transmission it will last a long time with the plate. Keep the rpms above 16-1700 loaded to keep transmission pressure up. My 95 got a plate at 112K and at 242K is still going! The plate never slipped the transmission locked. My 98 would slip the transmission with the #6 from the get go(116K) in OD at 24-26 psi. boost. I still towed with it to 185K without burning the transmission up by watching the boost gauge and tach.
DTT has a good explanation of checking transmission pressure and adjusting it on their site. I give that check and adjustment credit for the long life of my stock 47s.
My experience towing against a GMC 8. 1 with my 95 and #6 both with 8K TTs was the 8. 1 could beat me in stop and go traffic. If I could get locked up, the CTD could out pull the 8. 1. On a trip to Myrtle Beach I followed him and got almost 13 mpg while he got 6. 5 mpg. He soon after bought a CTD!

 

[TFucili]

My experience towing against a GMC 8. 1 with my 95 and #6 both with 8K TTs was the 8. 1 could beat me in stop and go traffic. If I could get locked up, the CTD could out pull the 8. 1. On a trip to Myrtle Beach I followed him and got almost 13 mpg while he got 6. 5 mpg. He soon after bought a CTD!

You are right on the money on the 8. 1. I had an '04 8. 1/Ally and it was a real hot-rod around town, but it really didn't tow worth a darn below 2500+/- RPM.

Then you combine the fuel economy with the small fuel tank in that Chevy, and you couldn't get any range at all.

 

[JoelAbq]

I plan to upgrade next year, but the way people seem to talk on these forums it's like your going to toast it in 12 seconds if your down to 2nd gear. I searched and searched and could not find any information on driving a heavier load with the stock auto trans and what to do. I found that I can sustain speed on a climb (and I don't mean race, I mean 30-40mph) and not build heat real fast if I manually shift down instead of letting the truck bog down in 3rd unlocked i don't build heat all that fast. Before I started driving it like this I could get the trans up to 220ish in in no time.



Later that trip when we came down to sight-see the durango train, I watched some half ton and 2500 pickups carrying less then me driving up at almost running speed for me. So even without a fancy transmission, I think if your conservative with your expectations and try not to get in a huge hurry while shift manually you can go a lot more places that you might think.



As far as the 8. 1/Ally, I agree with that above too. I noticed he can get around town a little easier, but once I'm locked and crusing I'm having the easier time. Even with likely 8500lbs extra weight attached, I'm impressed that my 6 cylinder 180hp truck still keeps moving almost as well as the 5000lb trailer I had before.



Joel