Overdrive issue and possible lifter tick.

[Reaper93]

Hello all; having issues with my 1993 Chevy suburban c1500 not liking overdrive and a possible lifter tick on passenger side of 350 tbi. She’s got 531k mileage on original engine and second 4l60e. Mechanic also said my ecu is on its way out. Would that cause any other issues?

 

[jjester6000]

Hello all; having issues with my 1993 Chevy suburban c1500 not liking overdrive and a possible lifter tick on passenger side of 350 tbi. She’s got 531k mileage on original engine and second 4l60e. Mechanic also said my ecu is on its way out. Would that cause any other issues?

Holy ****, 531k, congrats.

Sounds like your trans is losing 3rd/4th, first OD goes, then 3rd.

I had a '95 Burb C1500 that went 340k on the original trans before it blew a seal and lost all the fluid.

What would probably bring back OD would be some Lucas Stop Slip, it might prolong the life of your trans quite a bit.

At 325k, my trans had a harsh shift flare going into 3rd, so I poured in 2 bottles of lucas along with changing the fluid, and it lasted another 15k (I even drove most of the way across the country with it that way). It probably would have went further if I had the foresight to replace the rear bushing/seal, or have it towed instead of limping it 300 miles home.

 

[jjester6000]

Hello all; having issues with my 1993 Chevy suburban c1500 not liking overdrive and a possible lifter tick on passenger side of 350 tbi. She’s got 531k mileage on original engine and second 4l60e. Mechanic also said my ecu is on its way out. Would that cause any other issues?

How can an ECU be on it's way out?

There is nothing to wear, so what is it doing?

Also that lifter tick might just be a rocket arm out of adjustment, how does it run otherwise? Does it burn a lot of oil or smoke? How is the oil pressure?

If your motor is significantly worn, it won't have very good oil pressure, not allowing the hydraulic lifters to pump up very well.

Or it could just be some varnished up lifters which can be cleaned out with some seafoam.

 

[Reaper93]

Holy ****, 531k, congrats.

Sounds like your trans is losing 3rd/4th, first OD goes, then 3rd.

I had a '95 Burb C1500 that went 340k on the original trans before it blew a seal and lost all the fluid.

What would probably bring back OD would be some Lucas Stop Slip, it might prolong the life of your trans quite a bit.

At 325k, my trans had a harsh shift flare going into 3rd, so I poured in 2 bottles of lucas along with changing the fluid, and it lasted another 15k (I even drove most of the way across the country with it that way). It probably would have went further if I had the foresight to replace the rear bushing/seal, or have it towed instead of limping it 300 miles home.

I’ll try that, I need to change the trans fluid and filter but I’m afraid to due horror stories of the fluid holding it together, it leaks alil from the pan but not enough to worry to much. Last time I added fluid was a quart low but that was a month ago. Should I worry about the ecu causing issues with the trans problem?

 

[jjester6000]

I’ll try that, I need to change the trans fluid and filter but I’m afraid to due horror stories of the fluid holding it together, it leaks alil from the pan but not enough to worry to much. Last time I added fluid was a quart low but that was a month ago. Should I worry about the ecu causing issues with the trans problem?

What does the fluid look like? If it is dark, that's not the end of the world, but if there is junk in it, or it smells burnt, that's when I'd just pump a quart out of the dipstick tube and replace it with lucas.

What exactly is it doing? Is it slipping, or just not upshifting

If it's not upshifing, it is definitely a computer issue.

 

[Reaper93]

How can an ECU be on it's way out?

There is nothing to wear, so what is it doing?

Also that lifter tick might just be a rocket arm out of adjustment, how does it run otherwise? Does it burn a lot of oil or smoke? How is the oil pressure?

If your motor is significantly worn, it won't have very good oil pressure, not allowing the hydraulic lifters to pump up very well.

Or it could just be some varnished up lifters which can be cleaned out with some seafoam.

The mechanic said it needed to be replaced cuz it was throwing a temp sensor code and it’s still got the check engine light on even after he cleared it. Very minor smoking on startup but after that she’s fine. Oil pressure usually sits at 30. I do use high mileage 10w30 with Lucas oil stabilizer on oil changes. I tried seafoam but only in gas tank. How would I use it in the engine.

 

[Reaper93]

What does the fluid look like? If it is dark, that's not the end of the world, but if there is junk in it, or it smells burnt, that's when I'd just pump a quart out of the dipstick tube and replace it with lucas.

What exactly is it doing? Is it slipping, or just not upshifting

If it's not upshifing, it is definitely a computer issue.

It’ll have high rpms when I put in od, but in regular drive shes got no problems.

 

[jjester6000]

It’ll have high rpms when I put in od, but in regular drive shes got no problems.

So you get nothing in OD? Will leave off, or does it just slip in 4th?

 

[Reaper93]

So you get nothing in OD? Will leave off, or does it just slip in 4th?

She’ll rev high then shift up but that’s usually at 60mph and if it’s a hill she’ll downshift again then rev high again. I was thinking maybe the ecu was causing but now idk.

 

[kenh]

I'm not Mr. Transmission god, but at that milage and from your description I'm thinking the trans is due for an overhaul.

Pull the valve cover on the right side and see what's going on in there. Might be a simple adjustment???

Ken