ATTENTION: All Postings that advertise items for sale will be deleted from the Discussion Forum. You may post sale items for free in the Classifieds section. Sign up now.
I'm comverting from a Cat 3208 to 6v92 DDEC II with a HT748 with retarder. Can anyone tell me the basic difference between the HT748 and the HT740? Is one better then the other? I currently have a MT643.
There is not any real basic difference between any of the HT-700 series of transmissions. All of them have 5-speeds forward and one reverse. The different second and third numbers refer to specific applications.
The difference between the HT-700 and the MT-600 series transmissions is the amount of torque and H.P. the transmissions are designed to accept. A -700 behing a 3208 would be a bit of overkill. A -600 behind a 6/V92TA would be certain death within a very few miles.
The 'B' in the HTB-748 means the transmission has a retarder built into the transmission. Some are built into the front end and some are built onto the rear end. Which application you would use would depend upon how much room you have to work with between the engine and rear end. The retarder on the back end tends to make the transmission longer.
Some of the DDEC systems have to have the newer Allison transmissions with the ATEC in order for both of the units to work properly.
At this point, I am wondering why you are contemplating the change. The cost of all of the parts and pieces to changeover is going to cost you more than a good MCI/Prevost/Eagle that is already to go. I am also thinking the change isn't going to make all that much difference on the flat and on the upgrades you are going to have some real problems with keeping things cool if you try to use the full potential of the DD.
The reason I'm converting to 6V92 is because my BlueBird XV is a thing of beauty, with an extra foot of frame rail that allows the greater height of the 6V92. Engine, transmission and miscelleous parts for fabrication are less than $4,000. So... why not go for the power and hill climbing ability while having the fun of doing the conversion myself. After all, the only reason to own one of these old buses is for the fun of working on them.
email Doug
reply to message
post new message
search forums
