allisonman
Well-known member
- Joined
- Nov 11, 2009
- Posts
- 88
I have a 2009 Winnebago with the W22 Workhorse chassis and Allison 1000MH transmission with 3000 miles. Last week on a return trip on I26 from NC to TN there was a short period where the steep grade caused the transmission to shift to 2nd. The water temp went to 222 degrees and the RPMs were around 4000. The transmission apparently vented because my toad was lightly coated with trans fluid. I did a cold check of trans fluid level the next day and it showed to be about a half inch below the cold level mark. Is it normal for venting to occur in these conditions? The transmission had not previously leaked any fluid. Also, should I change the spin-on filter now rather than wait for the 5000 mile interval since the transmission was probably built in 2008?
that must have been a heck of a grade! ;D I've seen the dipstick calibration incorrect on some workhorse's ,causing a fluid overfill and venting. I've seen the tube itself not vented correctly causing fluid to come out of the rear vent. I would crawl under the coach and look at the vent at the top of the rear main case and see if there is trans fluid on it. the fluid on the toad could have been eng coolant overflow from the higher eng temp climbing the grade.
I would wait for the 5000 mile mark to change the filter. the trans if built in 08' would have not been driven more than a few miles in the bare chassis.