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-   -   TH-350 locking up in reverse?? (https://67-72chevytrucks.com/vboard/showthread.php?t=754229)

JQ-72 01-06-2018 06:42 PM

TH-350 locking up in reverse??
 
I just bought a 1978 1/2 ton 2wd from original owner with 97k miles, but it's been sitting since 2008. After plugs, fresh gas and 2 quarts of trans fluid, she's back to life! However, when I put it in reverse it bogs real bad and tries to go dead. I gave it about half pedal and it just sits there and bogs like the e-brake is on. What gives?? Thanks got any info.
Joshua

garyd1961 01-06-2018 08:56 PM

Re: TH-350 locking up in reverse??
 
Does it go forward when you put it in drive? If not the brakes are probably seized/locked up.

JQ-72 01-06-2018 09:32 PM

Re: TH-350 locking up in reverse??
 
Yes, I drove it about 150 yards to the end of my driveway then tried to turn around. That's when reverse locked up. I put it back in drive and drove it back to my house. I tested reverse again when I got to the garage and same problem.

andyh1956 01-07-2018 01:51 AM

Re: TH-350 locking up in reverse??
 
I bet your trans is in two gears at once. Most likely something stuck in the valve body or a band stuck from siting.

PGSigns 01-07-2018 10:17 AM

Re: TH-350 locking up in reverse??
 
Jack it up and try and turn the rear wheels with the trans in neutral and the truck not running. They should turn easily with a little drag. If they are tight pull the drums. After sitting that long there is a good chance the brakes need going through.
Jimmy

JQ-72 01-07-2018 06:04 PM

Re: TH-350 locking up in reverse??
 
Gotta be the trans. I tried it again today and now it stuck in drive no matter gear I put it in

PGSigns 01-07-2018 08:44 PM

Re: TH-350 locking up in reverse??
 
1 Attachment(s)
Have you jacked it up and checked the brakes? A truck that has sat that long with any amount of water in the brake fluid with have wheel cylinder problems. The more you push on the brakes the tighter things will get. I have seen this on many vehicles in my more than 40 years of working on cars. Having issues in reverse first and now all locked up is brakes.
Jimmy

Ironangel 01-08-2018 04:38 AM

Re: TH-350 locking up in reverse??
 
Quote:

Originally Posted by PGSigns (Post 8154643)
Have you jacked it up and checked the brakes? A truck that has sat that long with any amount of water in the brake fluid with have wheel cylinder problems. The more you push on the brakes the tighter things will get. I have seen this on many vehicles in my more than 40 years of working on cars. Having issues in reverse first and now all locked up is brakes.
Jimmy

Agreed...

Ironangel 01-08-2018 04:54 AM

Re: TH-350 locking up in reverse??
 
Quote:

Originally Posted by JQ-72 (Post 8154478)
Gotta be the trans. I tried it again today and now it stuck in drive no matter gear I put it in

If the rear wheels rotate freely yet the tranny is stuck in drive then the valve body has sticking valves. A half gallon low on fluid would indicate something wrong and if ran low like that before it was parked 10 years ago would just about cook a transmission. Drop the pan and see whats laying in the bottom of that pan. If it's full of mud start shopping for a good used transmission, they can be had for cheap from local junk yards and transmission shops...

cadillac_al 01-08-2018 10:30 AM

Re: TH-350 locking up in reverse??
 
I'm with Andy and something is stuck in your valve body. I would drop the pan and see what it looks like in there. I'll bet cleaning the valve body would most likely fix it but I would blow $22 and put a Transgo shift kit in it at the same time. If you look at Transgo's web site their trans video will show you how easy the valve body comes apart. I'm sure something is stuck in there.


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