sparky77

Got my 77 back on the road ,have about 75 + miles on her now.All new bushings,front and rear ,new shocks,all new brakes and lines,I rebuilt the trans th400 and the engine 350 L82.The drive shaft and the half shafts have all new universal joints ,took the drive shaft to shop and they checked the balance and it's good.So to the problem at low speed just barely moving in forward or reverse I'm getting what feels like a resistance and than it pops louse ,it will build up and than pop louse .Almost like when you pull the rope on a lawn more single cyl engine,you can feel the compression than it pops and the rope pulls easy .Also I've changed the lube in the rear end and put in the additive.Also rebuilt the trailing arm bearings.
Thanks,Pete

bazza77

Just a few things I would look at , without knowing what else you have , like how old are the tyres ! and assuming it drives alright at speed ,as in no vibrations ,no pedal pulse when applying brakes at speed (warped rotor? )
handbrake not binding ?

what about if your just rolling in neutral at that speed ? does it still do it ?

7T1vette

You put the posi-trac additive in the differential. Did you "exercise" the rear gear to loosen stuff up? You need to find a large parking lot and do some tight "figure 8's" to work that additive into the fluid and get some into the clutch plates. Start slowly and you might have some binding at first. But, with a few tight turns in both directions, it should free up. If not, you might have bigger issues in the 'punkin'.

P.S. If the half-shaft joints were not disassembled/reassembled in a way that would not put significant stress on the bearing yokes, resulting distortion could put them is a bind. That would be more noticeable at low speeds.

sparky77

Tires are new ,I'll go out and do some 8s and see if that helps.

Rescue Rogers

If the figure 8's dont work, jack it up and spin the rear tires by hand in neutral and see if you can re create the POP. then start removing the shafts to see where exactly the issue is

sparky77

Iv'e done that and the rear end spins free and no tight spots.

HeadsU.P.

H-m-m-m-m-m. Parking Brake internals?

sparky77

I was thinking could be ether the posi unit or could be I need a wheel ali. to set the toe on the rear wheels.

bazza77

It does make a big difference , trying to push a project around my yard between sheds with the tyres not aligned properly causes a lot of drag , but they never pop and release , just constant drag

<<< that's me after pushing

bazza77

what about the rear hubs , do they get extra hot after a drive (handbrake grabbing ? )

sparky77

No problem with parking brakes.I'll try and get her out this weekend and do some 8s it'll be fun anyway!!!!!

sstonebreaker

How far do you roll between pops?

domenic tallarita

Just a shot in the dark, but did the drive shaft shop remove any of the shaft ends and weld them back on? In 1971 I had a shop check my drive shaft and when I installed it it had a tight spot. I looked elsewhere and couldn't find a problem . So I decided to drive the car and fix the problem when it got worse and showed it's face.
It was the drive shaft, they didn't time the ends. also had a slight bend! What a poor drive line specialty shop.

Dom

sparky77

Well got my 77 out yesterday and did the 8s and no difference,I did notice that it's more apparent in reverse.I pulled the parking brake in both forward and reverse and that didn't make a difference.I don't think it's the rear differential because it does it going straight in reverse.

sstonebreaker it's matched to the wheel speed ,once every turn of the wheel.

stumpshot

I don't know much about it but did you spin the rear wheels with the swing arms hanging? If so, you might want to block them up to about ride height and see if anything changes. You checked the driveline u-joints, right?