Transmission (C6) problem/question

[Flagship]

I'm running a C6 behind my 7.3 - ex U-Haul. I have checked the oil level and it is in the operating range on the dipstick. However, If I stop really quick, the transmission goes into neutral for 30 seconds or so. If I add an "extra" quart of fluid, the problem goes away. I don't notice any frothing showing on the stick with the extra oil in there... but! I've been told that over filling is worse than under filling.

I know there's a bunch of knowledgeable C6 guys here, so.. What do I do? Run the oil high, or is something else causing my problem. It gets really embarrassing when I have to stop really quick in traffic and then can't move for a while.

 

[david85]

If I didn't know any better, I'd say your dipstick was off, or taken from the wrong vehicle. Uhaul trucks can sometimes have a strange service history. The only thing I can think of is to drain the fluid and measure how much to get out of the transmission and then compare that to the listed capacity.

Bear in mind, this is way past my bedtime and others here have forgotten more than I know about the C6, so you might want to wait for them to chime in first

 

[trackspeeder]

If it's not foaming, then leave it.

Yes, too much fluid will destroy a tranny. The fluid will foam when it enters the gear train. The foam (air) will cause the tranny to slip and burn up.

 

[Flagship]

And I will be able to see this foaming on the stick?

This tranny has a rear seal (where the driveshaft goes in), that leaks about 3/4 of a quart a year. I know darn well if I try to fix it, I'll end up having to pull the tailshaft housing to put in a new bearing, and having to put in a new yoke on the driveshaft and then I just know the tailshaft housing will leak or something.

Guess I'll just put in a quart of oil when it starts going into neutral and live with it.

Thanks!

Bart

 

[IDIDieselJohn]

It's an Ex-Uhaul truck..... i'm sure it's seen worst.



Drive it like a rental!

 

[trackspeeder]

It's an Ex-Uhaul truck..... i'm sure it's seen worst.



Drive it like a rental!

Could be worse.

Beat it like it owes you money.

U Haul trucks are fun to beat on. I mean drive.

 

[Flagship]

Could be worse.

Beat it like it owes you money.

U Haul trucks are fun to beat on. I mean drive.

Actually, it does owe me money! I spent a small fortune on this thing, I needed a truck that was as reliable as a new one, without the new price. So far, so good! I've now had it for about 5 years and have put in a vacuum pump, a set of glow plugs, a block heater and a couple quarts of ATF. Not counting the required oil changes.

It's in really good mechanical shape and I want it to last at least another 5 or 6 years!

 

[IDIDieselJohn]

You know, I wonder if the original dipstick broke, or someone stole etc. and U-Haul put one in from a Van?

The Van dipstick is longer....

 

[Flagship]

You know, I wonder if the original dipstick broke, or someone stole etc. and U-Haul put one in from a Van?

The Van dipstick is longer....

But, isn't it a *whole* lot longer?

I don't know, I guess I should take it to the shop, have them drop the pan, change the filter, check that the pickup is where it's supposed to be, put in the book specified number of quarts of oil and mark the dipstick. The only problem with that is the stupid converter drain down. You know, you leave it sit and the converter drains out and you have to wait after starting it before it'll move.

Really wish this thing had a hand shaker tranny!

 

[mariner45]

Unless I am missing something here, wouldn't it be much easier and cheaper to buy a replacement (new ) dipstick - then you will know for sure.

By all means guess away, but if it were me I would try and get the proper dipstick first. You might have the right dipstick or you might have the wrong one - only one way to find out.

I doubt if it will be much more than $30 and a heck of a lot cheaper than a fuid change that may not be necessary.

Thx

mariner

 

[Flagship]

Unless I am missing something here, wouldn't it be much easier and cheaper to buy a replacement (new ) dipstick - then you will know for sure.

By all means guess away, but if it were me I would try and get the proper dipstick first. You might have the right dipstick or you might have the wrong one - only one way to find out.

I doubt if it will be much more than $30 and a heck of a lot cheaper than a fuid change that may not be necessary.

Thx

mariner

Oh yeah, sure, common sense! Go ahead and take all the fun out of this!

Of course you're right. I was kinda in hopes that someone would say it's a common thing and that all you need to do is (fill in the blank). Perhaps a new dipstick is the blank that needs to be filled in! Guess I'll see if the dealership can get me one. Like you say, can't hurt.

 

[david85]

Another option is to just put the question to the forum and ask how long their dipstick is?

 

[trapper]

how long their dipstick is?

Longer than yours!

 

[Devilish]

When I took a trans rebuilding class in college Part of diagnostics was adding a quart. Your dipstick could be wrong but it has a factory part # stamped on it. You can lookup the part # online or call the dealership to verify it's proper application. Sometimes the trans filter slips causing the trans to suck some air. Dents on trans pan can also cause this. Adding fluid takes care of it.
IMHO due to age I'd take the rig into a reputeable trans shop for a filter/fluid change and general service. The service should include an assessment of trans condition band adjustment if necessary.

 

[trackspeeder]

Another option is to just put the question to the forum and ask how long their dipstick is?

Hmmm, don't think I will comment.