Trans overheat ?? Fluid loss !!

[Gregg]

Good morning guys,
This past week returning home I think I overheated my trans,
I usualy kick off the cruise control when it down shifts to 3rd and the rpm goes over 4k.
I was distracted on this particular climb
(Darn IPODS !!) trans was in 3rd, rpm was at 4300 and the cruise control was on.
My buddy behind us radioed me and said I was burning oil, turns out I had about a half quart of trans fluid loss from the over flow vent at the top of the trans.
Did I overheat my trans ??
Could the valve in that overflow vent be defective ??
Anyone ever experience this ??
Thanks,

[Gregg]

Good morning guys,
This past week returning home I think I overheated my trans,
I usualy kick off the cruise control when it down shifts to 3rd and the rpm goes over 4k.
I was distracted on this particular climb
(Darn IPODS !!) trans was in 3rd, rpm was at 4300 and the cruise control was on.
My buddy behind us radioed me and said I was burning oil, turns out I had about a half quart of trans fluid loss from the over flow vent at the top of the trans.
Did I overheat my trans ??
Could the valve in that overflow vent be defective ??
Anyone ever experience this ??
Thanks,

[speed racer]

I beleive you are ready for a fluid and filter change.

[RV 4 2]

Sorry to hear you had an issue. On larger hills, I kick off the curise too and climb manually. Personally, I really don't like turning that 8.1 over 4K RPM even though it can do it. I try to keep it below 3500 for my comfort level if I can.
Other than your buddy calling you and letting you know, were there any other indications from inside the coach?

[exrench]

What sort of hill were you dealing with and what were you hauling behind?

[knebrdr]

Greg,
It may be that the trans was just a slight bit overfilled and during that long haul it self leveled. We used to service a lot of vehicles from Bakersfield at a dealership I worked at in the San Fernando Valley and if you did a trans service on one of these vehicles and set the level at the full mark they would self level while going up the "Grapevine". Correct level is in between the lines or at the sight hole (depending)when at operating temp. If your trans was filled to the full mark at 150 degrees F it could very easily "puke" some fluid when it reaches 190/200 F during a long climb. I always prefer to set trans fluid levels at the add fluid mark because a mechanic can never duplicate the exact conditions that the vehicle will be operated under. Also remember that you can damage an automatic transmission easier by overfilling (aereation of the oil occurs) than by running it slightly underfilled.
Randy

[Gregg]

Mike,
No indications at all, no trans overheat indications, nothing.

exrench,
If memory serves me correct the hill was long and steep enough to cause my trans to down shift to 3rd, however it wasn't one of those hills that you crawl up at 30 mph,
I was towing my 04 Nissan Frontier, nothing extreem.

Randy,
Very interesting, good point.
I think I'll take speed racer's advice and have a trans service done.
Thanks guys !!

[DAN L]

gregg, i am going to get a scan gauge 2 this summer to primarily monitor the ally tranny temp. after i establish a baseline, i am going to install the amsoil synthetic tes295(?#) fluid.

[Max Hubrich]

Gregg,

Using the dip stick, does the fluid smelled burned? Should tell you a lot-- if no burnt odor, go with the filter and fluid change.

I ordered the Scan Gauge II yesterday from the manufacturer-- Two week delay in delivery, due to demand. I was told that they don't even advertise and can't keep up with orders. Go here.

I paid $169.95 (shipping is included). I know it is available for ten bucks less on other sites, ie. Ebay, etc.

[Gregg]

Dan,
Should be an interesting comparison.
Please post your base line temp info.

Max,
The fluid smelled nornal and looks fine, maybe just too full ??

[Duner]

Greg,
Now is the time to have Transyn fluid put in. I was at a FMCA rally where the Allison guy made a presentation. He couldn't stress enough how much better the performance is with synthetic. He said that it can run 30 deg cooler under load. They have field studies with city buses and dump trucks where they did tear down after 500,000 miles and can't see ANY wear.

I had a small tranny leak at the driveshaft that I had fixed just before the 3 yr warranty expired. Allison dealer must have put half pint too much in. No problems til about 6 months later I was pulling Cajon Pass and when I got to High Desert I had fine spray of fluid all over my white toad. It did not overheat, just hi revs in 3rd at the top of the pass. I got under there and mopped up all the wet parts of the back half of the tranny. A year and many hills later it never did blow out any more. Now I'm running synthetic.

[Gregg]

Thanks Bill,
We had the same type of fluid loss,
I am now planing to do a trans service and have Transyn installed.