However, building on Clifford's comments, if this is a sticking situation, I have to wonder what condition the transmission fluid is in. If it has not been changed in the past year or two (or?) I would consider changing it and the filter as a preventative measure.
The question becomes what fluid would you use if you decide to change it. Some folks go full bore and buy Transcend. I think Clifford has said in the past that Transcend is not necessary in an HT740. I had heard that Dextron and engine oil are acceptable.
I looked at an online owners manual for the HT740 (and other versions): http://manuals.chudov.com/M939-Series-T ... Manual.pdf
It appears that C-4 used to describe diesel engine oil. It appears that the current ratings are CK-4 and CJ-4 but they describe diesel engine oil.Hydraulic fluids (oils) used in the transmission are important influences on
transmission performance, reliability, and durability.
• Transmission fluid types recommended for use in the AT, MT, and HT Series
transmissions are TranSynd™, DEXRON® -III, and C-4.
• TranSynd™ is a fully synthetic automatic transmission fluid that meets new
Allison specifications for Severe Duty and Extended Drain Interval
. Please note that the tables showing fluid and filter change intervals are for
TranSynd™, Non-TranSynd™, and mixed transmission fluids.
• Some DEXRON ® -III fluids are also qualified as Type C-4 fluids. To ensure the
fluid is qualified for use in Allison transmissions, check for a DEXRON® -III or
C-4 fluid license, or approval numbers on the container, or consult the lubricant
manufacturer. Consult your Allison Transmission dealer or distributor before
using other fluid types; fluid types such as Type F, and universal farm fluids
may or may not be properly qualified for use in your Allison transmission
Clear as mud?
Jim
