Hello!
Before I start.. disclaimer I know absolutely nothing about transmissions but I am pretty good at following instructions. Also I am decent at taking stuff apart and putting it back together... for the most part.
I have a 1992 GMC K2500 with a 4L80E that has a really light reverse. It is an old county plow truck that is pretty beat cosmetically but only has 80k miles on it and engine runs strong. I use it to haul crap to/from my property but not looking to spend a ton of money on it. It was like this when I got it and I have been driving it like this for a few years. I just avoid using reverse. On a flat surface I can sort of reverse but really hard to get going. Once I get going though (like if I start nose up on a slight incline) I can keep going reverse no problem. Did a lot of reading on the subject and found it could either be a band of some sort that is worn out OR it is common for the reverse servo pin to get worn or sheered off. I can drive forward in all gears no problem including 1st.
From what I read the servo pin issue is fairly common and not incredibly hard to replace. I have already taken the truck to a transmission shop to attempt to diagnose whether or not it is the servo pin but didn't get a clear answer either way (full background story below). Decided to try the servo pin replacement myself to at least rule that out. Based on what I read all I had to do was drop the transmission pan and the servo pin was held in with 6 bolts. Sounded pretty easy and I found a replacement servo for cheap from Monster.
I have the pan dropped and was working on removing the 6 bolts holding in the servo. However I found one of the bolts is blocked by something with a plug going into it (photo attached). I can sorta get a wrench on the bolt but the bolt is way to long to clear that thing that is blocking it. There is one torx bolt that seems to be at least in part holding that thing in but it also looks like it is possibly attached in other ways. As I mentioned earlier I have no idea what I am doing so before I start pulling apart more crap and possibly damaging something I wanted to get a sanity check. Am I doing this right? Is this the right way to remove the 4L80E servo? Removing this part was not mentioned in the servo replacement descriptions I read online.
Transmission Shop Background:
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I called a transmission shop with decent reviews and asked them if based on what I was experiencing if they thought it might be an issue with the servo pin. They said they would need to check the truck out themselves but wouldn't charge me anything to do it.. fair enough. I took a couple hours off work to get over there when they were open. They hopped in the truck, tried to reverse for a couple seconds, and put it back in park. They said they would need $200 for a fluid/filter service so they could open it up and take a look inside.
I was a little underwhelmed by their "checks" so far but I had already made the effort to get over there and it made sense they needed to look inside to get a better idea.. so I went for it. They called me about 2 hours later and said "filter is FULL of material. Transmission needs a full rebuild. It will be $2,500-3,000". That is more then the truck is worth. I asked them about the servo pin. They said nope, needs full rebuild based on the amount material in the filter and I could come down to see it myself if I wanted... I was feeling like I was not getting the full story so I told them I would get back to them on what I wanted to do.
I then decided to show up at the shop without warning to see this filter. I didn't want to give them any time to prepare anything to "show me". When I showed up they seemed a bit caught off guard. Definitely got the sense they were trying to delay me. However it was a small shop so I just walked over to my truck and asked where the filter was so I could see it. There was a filter on the bench right next to my truck. They kinda pointed out a super light dusting of some sort of material on a small section of the filter but hardly noticeable.
I did some googling on what a filter full of material looks like and this was nothing close. I asked them again about the servo pin and they basically leveled with me that they don't really do repairs like that. They either do a fluid/filter service or pull them to be sent off for rebuild.. At this point I just told them to put the transmission back together and give me my truck back and I ate the $200.
Before I start.. disclaimer I know absolutely nothing about transmissions but I am pretty good at following instructions. Also I am decent at taking stuff apart and putting it back together... for the most part.
I have a 1992 GMC K2500 with a 4L80E that has a really light reverse. It is an old county plow truck that is pretty beat cosmetically but only has 80k miles on it and engine runs strong. I use it to haul crap to/from my property but not looking to spend a ton of money on it. It was like this when I got it and I have been driving it like this for a few years. I just avoid using reverse. On a flat surface I can sort of reverse but really hard to get going. Once I get going though (like if I start nose up on a slight incline) I can keep going reverse no problem. Did a lot of reading on the subject and found it could either be a band of some sort that is worn out OR it is common for the reverse servo pin to get worn or sheered off. I can drive forward in all gears no problem including 1st.
From what I read the servo pin issue is fairly common and not incredibly hard to replace. I have already taken the truck to a transmission shop to attempt to diagnose whether or not it is the servo pin but didn't get a clear answer either way (full background story below). Decided to try the servo pin replacement myself to at least rule that out. Based on what I read all I had to do was drop the transmission pan and the servo pin was held in with 6 bolts. Sounded pretty easy and I found a replacement servo for cheap from Monster.
I have the pan dropped and was working on removing the 6 bolts holding in the servo. However I found one of the bolts is blocked by something with a plug going into it (photo attached). I can sorta get a wrench on the bolt but the bolt is way to long to clear that thing that is blocking it. There is one torx bolt that seems to be at least in part holding that thing in but it also looks like it is possibly attached in other ways. As I mentioned earlier I have no idea what I am doing so before I start pulling apart more crap and possibly damaging something I wanted to get a sanity check. Am I doing this right? Is this the right way to remove the 4L80E servo? Removing this part was not mentioned in the servo replacement descriptions I read online.
Transmission Shop Background:
--------------
I called a transmission shop with decent reviews and asked them if based on what I was experiencing if they thought it might be an issue with the servo pin. They said they would need to check the truck out themselves but wouldn't charge me anything to do it.. fair enough. I took a couple hours off work to get over there when they were open. They hopped in the truck, tried to reverse for a couple seconds, and put it back in park. They said they would need $200 for a fluid/filter service so they could open it up and take a look inside.
I was a little underwhelmed by their "checks" so far but I had already made the effort to get over there and it made sense they needed to look inside to get a better idea.. so I went for it. They called me about 2 hours later and said "filter is FULL of material. Transmission needs a full rebuild. It will be $2,500-3,000". That is more then the truck is worth. I asked them about the servo pin. They said nope, needs full rebuild based on the amount material in the filter and I could come down to see it myself if I wanted... I was feeling like I was not getting the full story so I told them I would get back to them on what I wanted to do.
I then decided to show up at the shop without warning to see this filter. I didn't want to give them any time to prepare anything to "show me". When I showed up they seemed a bit caught off guard. Definitely got the sense they were trying to delay me. However it was a small shop so I just walked over to my truck and asked where the filter was so I could see it. There was a filter on the bench right next to my truck. They kinda pointed out a super light dusting of some sort of material on a small section of the filter but hardly noticeable.
I did some googling on what a filter full of material looks like and this was nothing close. I asked them again about the servo pin and they basically leveled with me that they don't really do repairs like that. They either do a fluid/filter service or pull them to be sent off for rebuild.. At this point I just told them to put the transmission back together and give me my truck back and I ate the $200.
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