Im New Here, New To Chevy Truck Club But Have Shifting Issue!

[CaptnC]

Just bought a 1995 1500 Z71 5.7L at a auction. So I have no history from the previous owner.

I have been in the automotive industry for a long time. Retired in 2019 with 43 years of service in a school bus shop. The last 20 years as a foreman.

So I had not been hands on as much as I once was.

The lack of history (198,000 miles) really didn't bother me too much, I can tell if someone did something and rough how long ago it was done just by looking at it.

So, here is the issue I have. The transmission seems to be skipping 2nd gear.

The trans pan been taken off quite some time ago. So it appeared it has been serviced, so I put a filter in it and fresh fluid.

I drove the truck 200 miles from the auction to my house. I babied it because I had not got a chance to really check the truck out until it was home.


So after the filter and fluid change I drove it a bit more aggressively. I'm not ready to drag race anyone but I did put my foot in it a bit. But not to the floor. You could feel the shift but it felt more like it was slipping, then going into third gear and finally hit OD.

While cruising at 55mph I stepped into it like I was going to pass someone. The engine free reved to 5000 rpm and I let off the throttle. It went right to third, then overdrive, back at 55mph.

The speedometer is off in an odd kind of way. Panel on the door jam says 265 75R 16. The truck had mis-matched tires. 265's in the front and 285's in the rear.

I bought a 4 tire set of 285 75R 16's for it before the trans service.

Large tires normally make a vehicle travel faster than what the speedometer, but this truck travels slower than the odometer.

On the way back from the auction I was not going over 70mph. But when I called buddy who I went with said I was barely going 60mph. He has oversize tire like I do and his odometer read 65, but he knows he is actually 5mph faster!

The first thing i checked when i going the truck home was the shift cable. Someone had been playing around with the adjustment but never push the white clip back in so the cover could cover it.

I have no idea why it's slipping?!?

 

[Deancr11]

Well I'm not an expert but I have an opinion. I'm guessing with the miles if it has not been rebuilt it's about time and if it has been rebuilt they did it wrong and well that would be a do over. Like I said that's my opinion that and $5 gets you a cup of coffee

 

[NickTransmissions]

Just bought a 1995 1500 Z71 5.7L at a auction. So I have no history from the previous owner.

I have been in the automotive industry for a long time. Retired in 2019 with 43 years of service in a school bus shop. The last 20 years as a foreman.

So I had not been hands on as much as I once was.

The lack of history (198,000 miles) really didn't bother me too much, I can tell if someone did something and rough how long ago it was done just by looking at it.

So, here is the issue I have. The transmission seems to be skipping 2nd gear.

The trans pan been taken off quite some time ago. So it appeared it has been serviced, so I put a filter in it and fresh fluid.

I drove the truck 200 miles from the auction to my house. I babied it because I had not got a chance to really check the truck out until it was home.


So after the filter and fluid change I drove it a bit more aggressively. I'm not ready to drag race anyone but I did put my foot in it a bit. But not to the floor. You could feel the shift but it felt more like it was slipping, then going into third gear and finally hit OD.

While cruising at 55mph I stepped into it like I was going to pass someone. The engine free reved to 5000 rpm and I let off the throttle. It went right to third, then overdrive, back at 55mph.

The speedometer is off in an odd kind of way. Panel on the door jam says 265 75R 16. The truck had mis-matched tires. 265's in the front and 285's in the rear.

I bought a 4 tire set of 285 75R 16's for it before the trans service.

Large tires normally make a vehicle travel faster than what the speedometer, but this truck travels slower than the odometer.

On the way back from the auction I was not going over 70mph. But when I called buddy who I went with said I was barely going 60mph. He has oversize tire like I do and his odometer read 65, but he knows he is actually 5mph faster!

The first thing i checked when i going the truck home was the shift cable. Someone had been playing around with the adjustment but never push the white clip back in so the cover could cover it.

I have no idea why it's slipping?!?

Band is likely worn out, time to yank it for overhaul. It's not slipping in 4th as both servos are applied while your 2nd gear servo (probably a 553) is the only servo piston applied when in 2nd gear. Having 33s isnt helping but assuming you have 3.73s it should be on the edge of "ok".

 

[CaptnC]

Thanks for the reply Nick.

During my early years I was the shop transmission rebuilder. According to my file I rebuilt 23 Allison transmissions 540, 543 and the 545. A bandless and services transmission. There was another guy who did the GM 350 and 400. I helped him a few times but mostly fabricating presses to service the clutches and servos.

Even though I have never been inside the case of one of these transmissions I'd trust myself doing the rebuild more so than taking it somewhere.

That said how much do rebuilders charge for a walk-in rebuild?

My preference would be to ditch the whole automatic trans and swap it with a manual trans. We're manual trans very popular in this model truck?

 

[NickTransmissions]

Thanks for the reply Nick.

During my early years I was the shop transmission rebuilder. According to my file I rebuilt 23 Allison transmissions 540, 543 and the 545. A bandless and services transmission. There was another guy who did the GM 350 and 400. I helped him a few times but mostly fabricating presses to service the clutches and servos.

Even though I have never been inside the case of one of these transmissions I'd trust myself doing the rebuild more so than taking it somewhere.

That said how much do rebuilders charge for a walk-in rebuild?

My preference would be to ditch the whole automatic trans and swap it with a manual trans. We're manual trans very popular in this model truck?

Those arent hard to rebuild, check out my 4L60E Information thread (link is in my signature line) for details, step by step video instruction, tips/tricks/mods and addl resources.

 

[movietvet]

Welcome to the forum from Oregon.

 

[CaptnC]

Thanks again Nick!

This trans must be pretty reliable, until I bought this truck, I had not realized there are so many still on the road. Mainly been a Dodge/Ford truck guy over the years. But, I'm picking up a clean 1971 C10 and a normally rusted 1978 4x4 next week.

The GMC line has always been my favorite look, this truck had always caught my eye, that's why I impulse bought it. My buddy took me just to get a feel for auctions and very surprised I jumped into the bidding! LOL

I live in a rural area outside of Houston Texas. I'm sure the illegal immigrants have brought a lot of these truck back from their grave, but I see a couple late 90's trucks every day. I drive a school bus part time and my route covers almost 130 miles everyday.

But anyway I will be checking out your video because doing a self rebuild is the easiest and cheapest path forward!

 

[NickTransmissions]

Thanks again Nick!

This trans must be pretty reliable, until I bought this truck, I had not realized there are so many still on the road. Mainly been a Dodge/Ford truck guy over the years. But, I'm picking up a clean 1971 C10 and a normally rusted 1978 4x4 next week.

The GMC line has always been my favorite look, this truck had always caught my eye, that's why I impulse bought it. My buddy took me just to get a feel for auctions and very surprised I jumped into the bidding! LOL

I live in a rural area outside of Houston Texas. I'm sure the illegal immigrants have brought a lot of these truck back from their grave, but I see a couple late 90's trucks every day. I drive a school bus part time and my route covers almost 130 miles everyday.

But anyway I will be checking out your video because doing a self rebuild is the easiest and cheapest path forward!

Sounds great, man and you're welcome...There's nothing like rebuilding something like an engine and transmission yourself, knowing exactly what went into it, how things were done and that they were done right.

Let me know if you have any questions along the way.

 

[Scooterwrench]

The first thing i checked when i going the truck home was the shift cable. Someone had been playing around with the adjustment but never push the white clip back in so the cover could cover it.

'95 shouldn't have a shift cable or were there still 700R4's in '95? I thought they had all been phased out by then.

 

[NickTransmissions]

'95 shouldn't have a shift cable or were there still 700R4's in '95? I thought they had all been phased out by then.

He's prob talking about the column shift cable that runs from the right side of the steering column to the transmission, not the TV cable. Last model year for the 700 was 1993 as far as I know.