TH350 only has R and L no D or 2

[bl78ljb]

Well, I have to admit this is slightly off topic as it is not in my diesel truck, however, I have been unable to get an answer from other sources and figured some here might have some insight. Well to start the saga off I had my tranny go south in the middle of a snowstorm almost 2 years ago at that time I lost reverse which is a common problem on plow trucks with the TH350. As I was not about to swap it out in below freezing temps I took it to a local recommended tranny shop, and it was rebuild supposedly with upgraded parts (I cannot remember what but I believe a 700 part is utilized to increase the strength of reverse). I was told "this should not break on you and if it does call me I stand behind my work, even if it is out of warranty [which was a year unlimited miles] as I know you don't drive it much." Well all worked well for the last few storms of the year, though I wasn't sure if it was upshifting into drive or not though it is hard to figure out as I don't tend to go that fast and with the wet snow here in Maine have a good foot into it. This last year while I was plowing I suddenly lost second and found that to get the truck to move forward at all I had to manually shift into first and then all was well in first but it would not upshift into second even if I tried to do so manually. I called the shop and explained that the truck only has 45 miles on the new tranny; and was told "since it is out of warranty I might be able to go 1/2 on the labor for you." At that I was not impressed so I thought I would look into it myself. Well, I procrastinated on looking into this and when I was doing some brake work this past week I noticed the vacuum line to the governor was off so I replaced it but to no avail. Now the snow is almost here and I am stuck either having to find another shop to fix this or fixing it myself, but I am not familiar enough with trannys to know where to start.

Thanks in advance.

[350Tacozilla]

take the line off the truck and blo compressed air in it.. if it was hanging down it may be blocked... also the modulator valve can go bad.... other wise it might just be the trans is going away internally

[bl78ljb]

line was replaced and is clear. The fluid looks fine so I wouldn't think it would be bands/ clutches especially with only 45 miles on the tranny.

[Yukon6.2]

Hi
Pull the govener,it's behind a round metel cap near the back of the trany.
It's got a plastic gear that can wear out or break off,causes the same simtons as you describe.Easy fix and best of all CHEEP FIX.
Traded a guy a rusted out suberban that had all the gears for a 88 Firebird that only had 1st and revese,i figered 1500 bucks for a rebuild,and install i'd have a nice clean Firebird, Learned about the govener,bought a $6 buck gear,the hardest part was getting the broken piece out with a mirror and a heated up wire.Incressed my profit margin by a bundle
Hopefully you'll get as lucky
Thomas

[bl78ljb]

Well, I pulled the governor today and it appeared completely intact and operational. I guess I will have to either keep looking (though with the temps dropping below freezing it doesn't take long for that to get old!), or find a shop that might stand behind their work to bring it to for further evaluation.