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Transmission Failing Signs

Big T

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Location
Fullerton, CA
On my '99 K2500 Suburban, I'm experiencing #1 and #7, particularly in the cold weather:

10 Warning Signs Your Transmission Is Going Out (+ What To Do About It) (cashautosalvage.com)

1. No Starting or Slow Starting
When your vehicle won’t start or is having trouble starting first thing, it may be a sign that your transmission is failing or has already failed.

Generally, this type of issue is more common in cold weather. The winter months can be hard on your vehicle.

A non-starting vehicle can mean many things, however, so diagnosing the transmission as the issue is something a professional may be able to do for you if that’s the case.

2. Gears Slipping
A transmission that is functioning as it is supposed to will stay in the gear that you select or the gear that it electronically is designated to be in. Once you or the computer within your vehicle initiate shifting gears, the gears will shift.

If your transmission is not doing this correctly, there is clearly something wrong. This can be a dangerous issue to have, regardless of whether or not your car is manual or automatic.

When the gears slip, it will pop the car out o the gear it is supposed to be in and may force it back into neutral. If you’re driving down the road when this happens, obviously it is quite dangerous.

3. Burning Smell
The pump in your car may not be getting the fluid circulating through the transmission as it is meant to. Because of this, the transmission will overheat and the fluid is going to start burning. This creates a putrid smell that won’t be pleasant.

It’s easiest to identify where the smell is coming from if you check the fluid dipstick. The fluid will likely be lower than it should be and it will be a darker color than it normally is.

Always check your fluids to make sure that they are where they should be.

4. Transmission Fluid Leak
Another problem with fluids is leakage. If you see that there is red fluid leaking underneath your vehicle, you need to get your transmission checked out straight away.

If you’re not sure whether there is a leak or not, you can put some cardboard beneath the car to catch any potential liquid that comes out.

After a while, you can check it to see where the fluid is coming from, what color it is, and how badly it is leaking.

5. Surging or Jumping
It can be scary when your car starts surging and jumping for no obvious reason.

One reason this may happen is if your transmission fluid or the transmission itself contains dirt and contamination. This prevents the fluid from flowing properly and can lead to the burning problem mentioned earlier.

There are other reasons for this issue, so it is not always the transmission, but it is worth determining if that is the cause of the issue. If so, you may need to get a new transmission or consider selling the vehicle.

6. Transmission Noise
Your car may be making weird noises and if this starts to happen, you should diagnose the issue right away. It may be more serious than it seems.

If the gears and the clutch packs are not lubricated with fluid pumped through the transmission, they may start to create friction. This can cause the noise, but it also causes premature wear and tear, extra space between parts, and slippage.

A bad transmission pump will lead to issues with the rest of the transmission in the vehicle. In addition, problems with the transmission can lead to problems with the pump.

This is why issues to do with low fluid, contamination, and worn out parts will make your pump and your transmission work a lot harder than they should. Eventually, they will fail due to excessive work.

7. Delay in Movement
Have you ever been putting your foot on the gas and your car takes a beat before it actually starts to move? This is a delay in the movement of the vehicle.

It may mean that your transmission is having issues, but more importantly, this is a huge safety concern. If you’re trying to pull out of a parking lot or turning left on a green light, you need to have an immediate response or you risk an accident.

If this is happening, you need to have your vehicle looked at by a professional as soon as possible to stay safe on the road.

8. Hard Shifting
Hard shifting happens when the transmission fluid isn’t pushed into the transmission at all. The gears don’t become lubricated as they are meant to and this causes significant wear on your gears.

If you have an automatic transmission, you will notice this when you feel a jerk or delay as you accelerate. In a manual transmission, it will be more difficult for you to get into the gear you need.

9. Check Engine Light
A check engine light can actually refer to a lot of different issues in your vehicle. It’s not always related to the engine, which is a common misconception.

A diagnostic machine can look at the specific error code that your car is exhibiting and it will diagnose where the issue is in the vehicle.

You can buy one of these machines for yourself or take it to a shop to have them read the code or you.

10. Grinding Gears
You may feel that when you change gears, there is a loud grinding noise.

It may be something you feel in your hand if you have a manual transmission. With an automatic transmission, your car may make noise or seem to have a hard time getting to the speed you need.

In this case, you may have worn out the clutch and that may be what needs replacement. In other situations, it may be that the transmission’s synchronizers need to be replaced because they are damaged or worn out.

Automatic transmissions that have a rough shift can mean a lot of things, so taking it to a professional to look at what is going on is a good idea.
 
I have seen several dodge trucks with the #7 issue especially when cold. some when dropped in reverse make a whine noise. my dodge makes the whine noise in reverse but doesn't have a delay.

when your's seems delayed, does it ease into moving or do you feel a slight bump when it catches. kinda like having your foot on the brake drop into gear and immediately feel the shift from park to a forward or reverse gear?

like WW says, check codes. normally the dash lights don't come on with tranny codes unless it's accompanied by an engine code
 
I have seen several dodge trucks with the #7 issue especially when cold. some when dropped in reverse make a whine noise. my dodge makes the whine noise in reverse but doesn't have a delay.

when your's seems delayed, does it ease into moving or do you feel a slight bump when it catches. kinda like having your foot on the brake drop into gear and immediately feel the shift from park to a forward or reverse gear?

like WW says, check codes. normally the dash lights don't come on with tranny codes unless it's accompanied by an engine code

It eases in, almost like a viscous coupling slowly locking up.
 
not sure how tranny codes can be read without a tech2 but how does the fluid look or smell. would you know how many miles are on the current fluid and filter? you might also check the condition of the cooler lines from the tranny to the cooler just to make sure nothing is pinched.
 
not sure how tranny codes can be read without a tech2 but how does the fluid look or smell. would you know how many miles are on the current fluid and filter? you might also check the condition of the cooler lines from the tranny to the cooler just to make sure nothing is pinched.

I just drained and replaced 4 quarts from it and the old fluid was slightly darker than the new. No burnt smell. Probably had 30K miles max on it, but that was spread over 6 to 7 years as it had not been used much. It has been doing this long before the fluid change, so don't go blaming that. Cooler lines are fine. I have a temp gauge on the transmission and it's rare to go over 140 F.
 
Might be one of them transmission pressure rental tools could help with the diagnosis.
I know the TH350 when the seals on the clutch packs gets bad, they sometimes takes a while before full engagement is felt.
 
I would make rounds to pull the pan, replace with a new filter and fresh fluid. even though you already drained in refilled with 4 quarts, the filter might be partially clogged. iirc didn't out have an aftermarket pan? does that pan have the oe magnetic inside where it will catch most if the debris and not allow it into the filter? if not, maybe it all is in the filter, again I am just guessing though.

I would asume you refilled it with dex 3 and not dex 6 as what GM changed to? stay with dex 3.
 
I would make rounds to pull the pan, replace with a new filter and fresh fluid. even though you already drained in refilled with 4 quarts, the filter might be partially clogged. iirc didn't out have an aftermarket pan? does that pan have the oe magnetic inside where it will catch most if the debris and not allow it into the filter? if not, maybe it all is in the filter, again I am just guessing though.

It has the OE Magnetic Plug. There was nearly nothing on it.
 
I would still recomend leaning towards a filter replacement just to have peace of mind. and go back with dex 3 fluid, but check the dipstick to make sure it calls for dex 3. just don't flush it or let a lube place mess with it.
 
I do recall that. it was a allen head bolt correct that was rounding off? now that I think about it, I have had some luck with using the tightest fitting torx bits and a 1/4" socket beaking them loose. maybe a metric allen. if not then it's dremeling the head off
 
I do recall that. it was a allen head bolt correct that was rounding off? now that I think about it, I have had some luck with using the tightest fitting torx bits and a 1/4" socket beaking them loose. maybe a metric allen. if not then it's dremeling the head off

I'm going to first try grabbing them with vise grips. However, there are 1 or 2 in the rear where that grab is not possible. Not going to do it this trip.

I don't this is imminent death on this transmission, so it can wait. No obvious sounds or other signs.
 
Just make sure it’s fully warm before a drive and take it easy under load paying close attention to any difference in feel and rpm to speed to monitor any slippage till you can tackle things
 
It eases in, almost like a viscous coupling slowly locking up.
That's what my 4L80E did in my 94 K2500. It acted like it lost it's "prime" so to speak especially when cold.
It failed shortly after that.
Hopefully you're not heading down that road.
 
imminent death on this transmission,

GM stuff tends to give you a warning before you walk. IMO you are being warned. I would find a transmission shop before the next trip. Loose fluid pressure and the clutches will burn up rather quickly.

It's possible the transfer case seal has gone bad and you have like two quarts from the trans overfilling it. The transmission needs the two quarts to work properly. Then foam or whatever gets stuck in the TC and is hard to get the fluid level up. Reads fine quits moving going around the block and takes quarts to bring it up again going around the block several times. No, don't drain the extra out of the transfer case as it will leak back into it from the transmission. You have to fix that seal if it's the problem.
 
After I get the upper control arms re-bushed and the knuckles reamed for the ES409RT tie rods, I get it aligned. Then I will take it in to the best transmission rebuilder here and just leave it. Tell him to do both the trans and the transfer case (4LO is not working). If not the transfer case, I have a place in San Diego that does rebuild exchanges.

Any specific instructions? Do I need Trans Go shifters?

BTW after the new injectors, It’s starting up nicely with not much smoke and it disappears quickly.
 
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