1984 k10 700r4 won't shift out of 2nd please help!

[NickTransmissions]

Hi! We recently bought a 1984 chevy k10 with a 700R4 transmission. it sat for about 14 months before we bought it, so we are chipping away at getting work done on it. It has been our daily driver truck but now is having a shifting problem that we can't figure out! This forum has a lot of great information so I'm hoping someone has an idea or can point us in the right direction.

Last month we had the intake gaskets replaced and a transmission service to change the fluid. Thing were working OK (truck still needed work) but it was shifting fine as best we could tell. The throttle had what felt like a hitch in it, you'd press it and it would get hung up, so you'd press it harder and the truck would sort of jump like something got unstuck. So we replaced the throttle cable and kick down cable and it seemed to be driving better, except we noticed that at first the truck was having a hard time getting into overdrive when going up a hill - we have heard that this can be common for 700R4 transmissions?

Throughout the process there were some points where the throttle would get hard and you couldn't press it down unless you put the truck into park to reset it and get the pressure off. So we were told to get the valve related to internal pressure in the transmission (sorry idk what this is called) replaced. At this time we also noticed that the overdrive shifting issue was becoming more of an issue. It was taking the truck a long time to get to 3rd - 4th and pick up speed in a way that was different from when we first got it.

We got the valve replaced and right away noticed that it wasn't shifting as smoothly, you felt it more and it was clunkier but the cable wasn't getting locked up. But the overdrive issue persisted especially when going up steep hills when not already at a high speed. When the trans shop replaced the valve they didn't have to drop the whole transmission. He also said that he didn't see any metal shavings or anything that would indicate a more serious problem.

Also, I don't remember exactly when it was done but we had the carb adjusted because it was having a hard time starting in the morning, so it was adjusted to a high idle that we had to kick down by punching the throttle before we drove. I wonder if this is related to the issue now.

We called the trans guy back and he didn't think our issue was anything major - he said we should just try driving it around in 3rd gear manual and see how it was. So we started to drive in 3rd gear manual and noticed a few times when accelerating uphill that it was now having a hard time getting from 2nd to 3rd. We would accelerate and feel the truck try to shift and the RPMs would increase, the engine would rev and try to kick up to 3rd but it would go back down to 2nd and then we'd eventually have to let off the gas and slowly ease back in and accelerate at a really slow rate. Eventually it would get itself from 2nd to 3rd

However...last night after filling up the tank with gas (premium), the truck drove the smoothest it has in a long time, shifted smoothly and even got up to overdrive until we had to come to a stop to make a left turn, deaccelerating from 55 to 0. Then after making the turn the truck could not get back into 3rd, it wouldn't shift beyond 2nd. Tried to drop it into park a couple times, turn off and restart but nothing mattered. Ended up having to drive home very slowly in manual 2nd. We also checked the trans fluid and it is clear/red without any metal bits or gunk that we can see.

We were told by the trans people to rule out the kick down cable or the throttle cable so we fiddled with them last night with no difference, still couldn't get out of 2nd gear. At this point we are unsure what to do, 2 transmission shops didn't think that it was anything major in the transmission but we have no idea. Could it be because of the high idle adjustment? or related to the carb since our Edelbrock is older. Not sure where to start since we are not well versed in older vehicles. Any help would be really appreciated!

Re-read the above, particularly your description about what's happening during the 2-3 shift and it does seem like your 3-4 pack is going out...Sometimes it starts out as a flare shift from 2nd to 3rd where RPMs jump for a second or two then 3rd engages at a slightly higher RPM than previous but progressively gets worse until you no longer have a 2-3 shift.

Checking pressure is still worth while because you want to know if there's a line pressure/line rise problem causing your shifting concerns...If so, you're dropping the pan, upgrading the boost valve and PR spring as well as installing Sonnax's 700R4 Throttle plunger and sleeve kit. If all this has already been done, and pressures themselves are normal AND pan is full of dark clutch material, it's time to yank it out and bring to your transmission builder for overhaul.

 

[Spookee]

Re-read the above, particularly your description about what's happening during the 2-3 shift and it does seem like your 3-4 pack is going out...Sometimes it starts out as a flare shift from 2nd to 3rd where RPMs jump for a second or two then 3rd engages at a slightly higher RPM than previous but progressively gets worse until you no longer have a 2-3 shift.

Checking pressure is still worth while because you want to know if there's a line pressure/line rise problem causing your shifting concerns...If so, you're dropping the pan, upgrading the boost valve and PR spring as well as installing Sonnax's 700R4 Throttle plunger and sleeve kit. If all this has already been done, and pressures themselves are normal AND pan is full of dark clutch material, it's time to yank it out and bring to your transmission builder for overhaul.

Thank you for this information! What would cause this to happen? It seems like it got worse after it came back from the trans shop with a new valve. What you outlined is way outside my scope of abilities so it sounds like I will be calling the local auto shop…

 

[Spookee]

that looks like a tv cable geometry bracket

with the engine running, how tight is that slack in that tv cable(bottom bracket)

It is tight when the engine is running, top has slack

 

[Spookee]

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I cant tell what carb it is either but it appears to have the same brackets asd a 1406 edelbrock, but the throttle opening and the idle cam either are somehow active or are grossly not set right.. on .. now which one is it?
here is my linkage with nothing on it

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Assuming it is an edelbrock type carb, it just appears to be forward much more than its supposed to. or, rather, rearward,. too vertical. so the geometry may not be right

Thanks for this! It is an edelbrock carb I’ll try to get a photo of it tonight after work and post it here

 

[Spookee]

I hate to suggest it, but when you mention now it tries to go to 3rd but it's not there and slowly goes back to 2nd, sounds to me like the 3/4 clutch pack may be toast now. You got to realize, if that TV cable isn't set correctly, it doesn't take long to cook that 3/4 clutch pack and if it's huntin' for 3rd but it's not there is what's telling me 3rd might not exist anymore. Now if you'd have said it won't go to 3rd, then I'd say it could be something else. A new @NickTransmissions would probably know better than anyone. I've gotten way rusty and forgotten a lot now.

Thanks for this information! It won’t go into 3rd anymore. We are now stuck at 2nd gear. The rpms increase and you can hear the engine rev like it wants to but nothing happens

 

[Spookee]

THAT MAKES me think your shifter cable and linkage isnt properly setup, because if its not reflecting the righht gear position, then there is a chance your gear shifts arent matching the detents on the column. its very important the detents match the proper position for the shift valve thingy inside the trans

That makes sense! I’m not sure why it doesn’t show us position on the shift window. It came like that when we bought it

 

[NickTransmissions]

Thanks for this information! It won’t go into 3rd anymore. We are now stuck at 2nd gear. The rpms increase and you can hear the engine rev like it wants to but nothing happens

The 3-4 pack is smoked...Drop the pan to confirm but it will need to go back to the shop for rework. Once you get it back and installed, you must perform a pressure test to validate your TV cable set up and adjustment are good to go...I give all my 700R4 and 200-4R customers detailed instructions for cable set up and adjustment along with a pressure readings chart to compare their pressures against the reference values. Meanwhile, flush all of your lines, cooler(s) to make sure any burnt clutch debris has been removed, otherwise you'll have a return restriction and destroy your rear gear train in the first few drive cycles.

Did your transmission builder do the same or talk you through the importance of setting/adjusting the TV cable and using a pressure gauge to dial it in?

 

[Bextreme04]

That makes sense! I’m not sure why it doesn’t show us position on the shift window. It came like that when we bought it

It's very common for the needle, or link cable, or plastic guide to break to the indicator. Any of these breaking will cause the needle to no longer move when you move the shift lever.

 

[Spookee]

It's very common for the needle, or link cable, or plastic guide to break to the indicator. Any of these breaking will cause the needle to no longer move when you move the shift lever.

Thank you, mystery solved

 

[Bextreme04]

Thank you, mystery solved

Not sure why I didn't notice this before... but your truck is the same color scheme as mine... and you guys are also in Oregon

Where are you guys located? What shop have you been using for your trans work? It really sounds like they don't know what they are doing(NOT uncommon, especially for the older stuff).

 

[Spookee]

Not sure why I didn't notice this before... but your truck is the same color scheme as mine... and you guys are also in Oregon

Where are you guys located? What shop have you been using for your trans work? It really sounds like they don't know what they are doing(NOT uncommon, especially for the older stuff).

Florence area! We had to drive over to Eugene to get the valve replaced at Advance transmission. There isn’t really anyone over here that does the internal trans work that we know of

 

[Bextreme04]

Florence area! We had to drive over to Eugene to get the valve replaced at Advance transmission. There isn’t really anyone over here that does the internal trans work that we know of

ooof, that's not good. I'm just up in Salem. There is a facebook group you should check out called Eugene / Springfield Square bodies. There's quite a few members in the area and I'm sure someone on there could recommend a good transmission shop that is experienced with 700R4's to help you out. They also do regular meet ups in the Eugene area during the summer, which is fun.

I had recommended a shop here in Salem that was very experienced and knowledgeable to another member several years ago, but he retired last year and moved out of the area.

I usually end up around Florence area a couple times of year. I used to do the Oregon Dunes triathlon down there every year and my family likes to camp at Honeyman a few times a year too.

 

[Spookee]

ooof, that's not good. I'm just up in Salem. There is a facebook group you should check out called Eugene / Springfield Square bodies. There's quite a few members in the area and I'm sure someone on there could recommend a good transmission shop that is experienced with 700R4's to help you out. They also do regular meet ups in the Eugene area during the summer, which is fun.

I had recommended a shop here in Salem that was very experienced and knowledgeable to another member several years ago, but he retired last year and moved out of the area.

I usually end up around Florence area a couple times of year. I used to do the Oregon Dunes triathlon down there every year and my family likes to camp at Honeyman a few times a year too.

Thank you SO much for the tip! I will check it out. I don’t have a Facebook but will make one just for this… I’m really at a loss for what to do right now other than call around the auto shops. So I will definitely reach out to the group. Thanks again I really appreciate it!

 

[Bextreme04]

Thank you SO much for the tip! I will check it out. I don’t have a Facebook but will make one just for this… I’m really at a loss for what to do right now other than call around the auto shops. So I will definitely reach out to the group. Thanks again I really appreciate it!

I put a question on the group looking for a good shop, so if you join you'll likely see it on the top of the feed. Hopefully there will already be some responses on there. Its a solid group and the admin is a great guy(BJ Parden) who has lived in the area for a very long time. The only thing I know about that Advance Transmissions is that their reviews are terrible on Yelp.

 

[AuroraGirl]

Thank you, mystery solved

Not necessarily guaranteeed tho, do your shift detents on the column match cleanly the ones on the trans> fi they do, you dont have to worry, but if you shift it down, say, 2 spots, you are very clearly in reverse? If ylou go down 1 from there youre in neutral? and when you do that push the shifter forward to the dash to slowly travel each detent