TH400 Dipstick "Depth"

[howardjnl]

Folks, helping a friend with his former US Govt. maintained 6.2 diesel, TH400 1 ton truck. Replaced the locked up engine with a govt. surplus 6.2 from HV, works terrifically. HOWEVER, TurboHydramatic 400 will shift into reverse and 1st just fine, but will not upshift into 2nd or 3rd.

Truck has been sitting for about 9 months before trying to drive it. Modulator valve vacuum line was NOT connected when I started this engine swap. Original TH400 dipstick from the govt had a splice in it, was so long as to hit the bottom of the transmission pan. Current owner said he always had to fill transmission above fill line to get it to work.

So, I reconnected vacuum line and I replaced dipstick and tube with new ones so that bottom of dipstick is about 1 inch below the end of the tube. Filled transmission to new "full" line.

No 2nd or 3rd, tried disconnecting vacuum line to make it like it was: no change. Wondering if new dipstick is indeed correct, as new fill level is about 3 inches or more higher than it was with old dipstick. This fills transmission pan, with engine off and cold, up to about 1.5 to 2 inches below its top. Does level sound about right?

John

 

[DeviousK5]

Do yourself a favor and get a fitzall dipstick, they're universal cut-to-fit tube.
I am betting on a stripped governor gear stopping you from upshifting though.
As far as the fill level, there was a deep pan and a shallow, you would have to know which to make a determination(ghetto determination) of how full it is. Running i would venture to guess that the level will be about 3/4 to an inch below the case.

 

[howardjnl]

Pan is deep, between 3 and 4 inches. 3/4 to inch below the case is about where it is now. With orginal crappy stick was about 3/4 inch or so above the bottom, about 3 inches below the case. Thanks!

 

[ramjet gmc]

i tried to put in a oem dipstick in my rig and it should have been a E-Z fit but it was more trouble that the trans swap

i got a locar cut to fit and that was the ticket

 

[76zimmer]

I've used a few of these, and had good results with em:

http://www.coanracing.com/Catalog.asp?ProductDetail=655http://coloradok5.com/forums/showthread.php?t=272598

 

[Greg Ducato]

Your no upshift condition would not be caused by low fluid level. If you have verified that you have good vacuum to the modulator, then pull the governor and check the gear, it may be "apple cored' or broken. Also, be sure there is not a contant 12 volts to the case connector leading to the kickdown solenoid. Some times the kickdown switch can stick or malfunction.