Intermittent trans issue, possible wrong fluid?

[Drock]

Okay I'll try and make this short, but I want to explain it all. I changed the trans fluid, and swapped the pan out for a after market deeper one. The gasket that came with the new pan failed spraying trans fluid EVERYWHERE! So I degreased the whole underside of the truck, Installed a new gasket. And now no more leaks. While all this was first going on I was smelling hot trans fluid and sometimes when I would put the truck in park , then back into drive it wouldn't go into gear without standing on the gas! I figured these issues were both from the leak. Once moving it was fine....... So now that I've fixed the leak I'm still getting the hot trans fluid smell and every once and a while it won't go into gear from park? I used (Valvoline Max life) fluid which says it's DEX III compatible.

 

[Chaski]

I am no transmission expert, but it it won't move without lots of throttle it sounds like more than one set of clutches (or bands) is engaging.

 

[cucvrus]

I am thinking the deeper pan may have moved the suction pick up point. How deep is this pan you replaced it with? The deepest pan I knew you could put on a CUCV without changing the pick up tube/bolt/spacer was the HMMWV 400 trans pan with the drain plug. After that I was told the filter hangs to much at an angle and the filter needs to be completely submerged or it will suck air and crate a hesitation/delay in the shift action. Not sworn to know if that is true but worth a look. I hope that helps a wee bit.

 

[dmetalmiki]

Why change the pan? the old adage comes to mind here.."if it ain't bust Don't fix it!" That pick up may be non aligned as said before. It always puzzles me why people do radical changes on systems that (have) functioned for years with absolutely no problems whatsoever.

 

[Drock]

Why change the pan? the old adage comes to mind here.."if it ain't bust Don't fix it!" That pick up may be non aligned as said before. It always puzzles me why people do radical changes on systems that (have) functioned for years with absolutely no problems whatsoever.

I agree with keeping things simple or stock for the most part. However I use this truck as my daily driver and work truck towing and hauling heavy loads down the highway. I added a banks sidewinder turbo and a Gearvendors overdrive to help with that. The truck was getting a little hot on the highway. So I added a Trans cooler and a derale deep trans pan with cooling tubes to also aid in cooling. The pan came with the proper filter and gasket. If it's sucking air could I run it a little fuller? Would this cause a problem?

 

[porkysplace]

I agree with keeping things simple or stock for the most part. However I use this truck as my daily driver and work truck towing and hauling heavy loads down the highway. I added a banks sidewinder turbo and a Gearvendors overdrive to help with that. The truck was getting a little hot on the highway. So I added a Trans cooler and a derale deep trans pan with cooling tubes to also aid in cooling. The pan came with the proper filter and gasket. If it's sucking air could I run it a little fuller? Would this cause a problem?

Was there a lot of sludge in the old pan when you changed the fluid ?

 

[Drock]

No it was actually really clean other then it was the original factory fluid.

 

[cucvrus]

After reading everything you and others posted. I am thinking it may be time to have that transmission pulled out and gone over. With all the changes and the age of the vehicle a good thorough freshening of the transmission in in order. From the sound of it and your description it is the weak link in the drive line and is the most neglected part most times because of cost. Also the torque converter could be checking out on you. You did not elaborate on the condition of the transmission but I know in the past you mentioned over heating. Transmissions can do that also. Good Luck but I think you are avoiding the inevitable.

 

[Drock]

Well hope you're wrong, it was working fine until I changed the fluid. And it still shifts perfectly. I just added another quart of fluid .I'll find out tomorrow if that helps. I still wonder if this is the wrong fluid?

 

[cucvrus]

Many times in the past I had seen transmission trouble when i drained the transmission and changed the fluid and filter. Old clutches and transmissions do not like to be messed with and serviced. I have seen it before. You have cleaned everything and the pressures have changed and that can do no harm but make things work better and they are not up to it anymore.

 

[rsh4364]

What is your cruising rpms in overdrive?,if lower than stall speed of convertor it will create lots of extra heat,frying the bands.If your pan has a bung for it add a trans temp gauge, I love gauges cheap insurance.That's the same fluid I used back in July when I changed my fluid and filter, mine is also a daily driver, 500 miles a week.

 

[Drock]

What is your cruising rpms in overdrive?,if lower than stall speed of convertor it will create lots of extra heat,frying the bands.If your pan has a bung for it add a trans temp gauge, I love gauges cheap insurance.

I don't have a RPM gauge so I can only calculate. .456 gears and 31" tires.Not sure what the final drive is on the Gearvendors?

 

[overlordofmars]

You ran low on fluid, now from lack of fluid during that time you damaged the the torque converter , and your first gear clutches. Are likely burnt. Not to mention the vanes in the pump are worn. I hate to say it, but your leak cooked it. As your dip stick sets the fluid level, I do not see a problem with a pan change. I have a plus 2 quart finned pan on my m1009 with no issue. That's my best guess from the dozen or so TH400 series transmissions I have had over the years.

 

[porkysplace]

You ran low on fluid, now from lack of fluid during that time you damaged the the torque converter , and your first gear clutches. Are likely burnt. Not to mention the vanes in the pump are worn. I hate to say it, but your leak cooked it. As your dip stick sets the fluid level, I do not see a problem with a pan change. I have a plus 2 quart finned pan on my m1009 with no issue. That's my best guess from the dozen or so TH400 series transmissions I have had over the years.

I believe you are correct about the transmission being toast , this is a ongoing problem from the looks of it since the gear vendors overdrive was installed . There has been a overheating problem for awhile now . He was asking about thick transmission fluid 3 months ago . It's time to bite the bullet and have the transmission rebuilt .
Related thread : Trans fluid question?

 

[Tinstar]

As the old saying goes;
"You can spend a little now, or a LOT later"

Sounds like later is here

 

[overlordofmars]

TCI makes one heavy duty TH400 replacement , but the last one I bought was $1400.00 complete with fluids and torque converter. They had a towing / HD transmission I installed in our 3500 Chevy that had a 6.2 with a banks turbo. It's still going and shifting smooth 7 years later with about 80k more on the clock.

 

[MarcusOReallyus]

I used (Valvoline Max life) fluid which says it's DEX III compatible.

The LO calls for Dexron II, so your MaxLife Dex III is just fine. Some guys run Type F and swear by it. I don't think your fluid caused the problem.


I'm really wondering about a gasket that sprays fluid all over the place. All I've ever gotten was a leak. Something about that just doesn't seem right, but then, this is my first TH400, so maybe I don't know what I'm talking about.

 

[Drock]

The LO calls for Dexron II, so your MaxLife Dex III is just fine. Some guys run Type F and swear by it. I don't think your fluid caused the problem.


I'm really wondering about a gasket that sprays fluid all over the place. All I've ever gotten was a leak. Something about that just doesn't seem right, but then, this is my first TH400, so maybe I don't know what I'm talking about.

yeah it came with the pan. It looked like a composite and when it started leaking I figured it was something I did wrong. But when I pulled the pan the fluid had seeped right through the gasket. And looked like cardboard. I replaced it with a felpro rubber gasket and it's dry as a bone now.

 

[overlordofmars]

The TH400 is usually a bullet proof transmission. Its only when they get damaged or hurt that they act like your describing !

 

[Drock]

Update.. So it's bin a little over a month sense I over filled the trans to see if that fixed the problem. And it did,.. well sort of. I stopped buy the local trans shop and talked to the owner who was VERY knowledgeable. He looked at it and said the trans is not damaged and the problem probably was do to the fact that I hard mounted the filter using a spacer. So I went home and pulled the pan to remove the spacer and found that the extension tube had somehow collapsed on itself where it pushes into the trans. And tore one of the rubber O-rings. I replaced the extension tube with the original (Good thing I kept it) and 2 new O-rings, removed the spacer, then reinstalled it with the same rubber gasket. It's bin problem free for the past 2 weeks of daily driving so hopefully this fixed it. If not the shop owner quoted me a really good price of $725.00 to pull & rebuild the trans.