renner

Well today I took the truck to Van Burean automotive ,Strictly a Allison dealer. Anyway I got there and they hooked up the laptop and ran thru all the parimeters while driving the truck. It was pretty cool he could see if there was any clutch slippage, overheat, torque converter slip, low fluid level, you name it it could tell you what its been thru. Basically the trany has never had a problem , no codes, all the sensors are working properly. What he did do is totaly clear the shift history and lowered the gear it will downshift into during engine braking which will help it slow down.Clearing the shift history will let the trany re-learn with the first 500 shifts. He also told me he has driven many Macks with this very same setup and mine feels exactly the same, he also told me that he thought that Mack could re-tune the ecm to a little higher HP rating which would help the truck pull out of the gear shifts from 3-4 and 4-5 which are the widest spread.I guess all in all its a learning curve, just so used to rowing gears. Thanks for all the input and advice and will let you know how she runs loaded after a full day behind the wheel.

It takes off fine, shifts 1-3 right where I would shift myself (Talking loaded). its the third to fourth spread, motors has to be flat out on the govener so that when it shifts it won,t dog out in fourth as the rpm drop is about 600 rpm and she falls off her torque curve and you basically flounder along not making any speed and if there is any and I mean any kind of hill forget it. the trany has a .67 OD but 5th gear is 1.00. rear ratio is 5.06. I am going to try a Allison dealer on the island to see if they can re-program it as a friend of mine runs a septic truck with almost same setup and he drove it sunday and said something isn,t right. As far as the 8LL goes yes I would have to get the OD one as thr rear ratio is pretty low, but like I said 55 mph is very rare around here on our roads, truck never sees the highway.Thanks for all the replies very helpful.

Eastern Long Island , Sag Harbor. we have Gabrelli Mack on the Island, but they aren,t exactly cheap or friendly.Only go there in a pinch.

Thanks for info Green Giant 2

I don,t know my 2000 Volvo with 330hp DD 11 liter with an 8LL will run circles around the mack, same wheelbase, same tires, and same body. It needs more gears . Most guys around me have the same engine setup with 8LL and they are fine. Even manually shifting doesn,t help much, Another part is stopping the engine brake and trany just don,t work together and we are roaring thru brakes. Most of our driving is around rural roads not much more than 50mph, lots of stop and go and fair amount of off road.Its my mistake for not researching the auto first but I am into this thing now and it sits in the yard as nobody wants to drive it and we all want to use the older trucks. I have a line on a trany ,bellhousing and driveshaft, talked to mack already not a big deal re-programing ecm. Just don,t want to buy new pedals and misc stuff direct from Mack. Its a lot cheaper than having it sit around not used. no one knows of a dedicated Mack salvage yard that a private person can buy from?

Hi all new to forum, I didn,t want to jump on the other topic about auto to standard. Anyway I want to swap my allison4560 that's in a 2006 granite triaxle dump with a E7 375hp for an 8LL. just purchased truck not long ago and am very disappointed in performance of trany, just not suited for my area and use. I wanted to know if any of you know the best Mack salvage yard in east coast to go to for all the small parts as in pedals/cables and mounts. thanks in advance