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Re: Allison Transmission Question
harold1946 wrote: wolfe10 wrote: Actually, Workhorse is the one who installed the transmission and selected the transmission fluid.No!! Allison fills the transmission and delivers it to the chassis builders. Allison also dictates which fluids can be used. They or your Workhorse manual would be your best source if info assuming there is not a "Transynd" label on or near the transmission dipstick. Sorry Harold, but Allison supply the transmissions without oil. The chassis manufacturer fills the transmission after it is installed and all cooler pipes etc have been fitted. Fitting the cooler pipes to a full transmission would make a hell of a mess. Allison produce oil specifications for their transmissions, and also have a list of approved oils, but the chassis manufacturer chooses what the initial fill will be. As long as it meets the specs it is ok. Transynd often has a horrible brown colour when it has been in service for some time. When you buy a used vehicle it is probably a good idea to change ALL the fluids if you intend to keep it for some time.282Views0likes0CommentsRe: Starter Solenoide
I assume that by "advanced position" you mean engine crank position? The coil in the starter slave solenoid is only powered up while cranking the engine, so shouldn't be on long enough to heat up. The current through the contacts is only for the pull-in and hold-in coils in the main solenoid on the starter. This should be 80 - 100 Amps very briefly as the starter engages the ring gear, and then drop to 10 - 20 Amps as the starter cranks the engine over. This also should not cause the solenoid to heat up. Starter slave solenoids should be intermittent rated, rather than continuous rated. Continuous rated solenoids can latch on if there is corrosion in the circuit. Intermittent rated solenoids also tend to have stronger contacts.423Views0likes0CommentsRe: What Alison tranny do I have??
With the push-button shifter you have a 3000 series. It is a full fly by wire system. 2000 series have a T bar type shifter with a mechanical pull cable down to a lever on the lower left side of the transmission. ID plate is on the right side of the transmission.242Views0likes0CommentsRe: Exhaust or jake brake or neither?
The Allison ECU with a MD3000 will activate the exhaust brake automatically when the following conditions are met; Torque converter in lockup, Throttle pedal released, Dash mounted exhaust brake switch is on, Cruise control not active, ABS not active. The exhaust brake works independently from the foot brake, but some vehicle manufactures wire a switch into the system requiring the brakes to be applied before the exhaust brake operates. Others will fit a foot operated switch that has to be pressed. When the ECU activates the exhaust brake, it also switches to a secondary shift schedule that downshifts the transmission earlier. This is done to keep the engine revs higher to increase the exhaust brake performance. It is also possible to force downshifts even quicker by programming the Exhaust Brake Preselect Parameter to a low gear, eg 2nd. The options for this parameter are gears 2 through 6. When the exhaust brake is activated the display will show the preselect gear that is programmed in the ECU. The display will only change if a lower gear than the normal top gear is programmed. Selecting 2 can be a bit brutal as the transmission will try to downshift to 2nd gear as soon as possible. 4th is often a better choice. At low engine speeds in a high gear the transmission may drop two gears when the exhaust brake activates. As previously advised it is often suggested to go down a hill in the same gear and engine revs that you would go up it. If you would go up a particular hill at 1800rpm in 3rd, then it is probably a good idea to manually select 3rd and use the exhaust brake to hold the engine speed at about 1800rpm going down. This will depend on how effective your exhaust brake is. You should always manually select the gear when going down a hill, don't just leave the selector in D. The transmission is likely to upshift, instead of downshifting to keep the engine revs high for maximum exhaust brake retardation.354Views0likes0CommentsRe: Starting problems 1992 Safari Ivory Diesel
Common electric starting systems for diesel engines; 12volt - one or more 12v batteries wired in parallel, 24volt - two 12v batteries wired in series, Series-parallel - two 12v batteries are connected in parallel to give 12v for normal running. The batteries are switched to series for 24v starting. The batteries are switched back to parallel once the engine starts. I believe that 12v is the standard for on highway in North America. 24v is very common in other parts of the world. Series-parallel doesn't seem to be used much any more. Some installations may have two 6v batteries instead of a 12v battery.454Views0likes0Comments
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