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Yukon6.2
04-20-2024, 10:28
Hi All
I had to move my nicest Sub the other day. Put in a fresh battery and fired up and purred away.
It was my Mom and Dads for years. It started life as an Olympic Officials truck at the 1988 Winter Olympics in Calgary.
I got it back a few years ago still in great condition, but someone took the plaque off the dash that told of it start in life, and the tranny has issues
It has forward motion,but doesn't really shift like it should.
No reverse, when it's in reverse you can floor the skinny pedal and the motor doesn't rev up. It sounds like it's under load but nothing happens.
In Neutral it tries to move forward, but the engine revs up while trying to move.
Oil doesn't really smell burnt
Anyone have a direction to point me in or is it in need of a tranny.
Thanks7588

arveetek
04-29-2024, 07:37
Sounds like a broken band inside the transmission. Unfortunately, it's going to require rebuild or replacement.

Casey

Yukon6.2
04-29-2024, 08:16
Thanks
I was hoping it would be something simple,but oh well it is what it is.

Robyn
04-30-2024, 06:51
I assume it is a 1500 series ???

If so the tranny is a 700R4

Gonna need to get that box out and on the bench.
There are several things that can cause the issues you describe....

The 700R is not hard to go through.....

If you want to get an idea.....get the rig in the shop and carefully drop the pan......

Good bet it has a lot of broken metal pieces in the pan (Shavings)

Gonna need to come out and apart....

If the case is not damaged the box can be repaired....

Keep us posted as to what you decide to do and or find.....

I'm very curious as to whats broken.......
Reverse input clutch (Up front just behind the pump) .....Low reverse clutch (At the rear of the box)

Why is moves in "N" ?????? Parts ground up ??????

Yukon6.2
04-30-2024, 08:26
Hi Robyn

Yes it is a 1500 with the 700R4
It moves forward just a bit in Neutral,not enough to actually move anywhere. Just enough to give a bit of forward motion like an inch, and doesn't move at all in reverse. It acts like it's working against it's self in reverse as the engine will not rev up with the skinny pedal to the floor.

Chances are it will not get looked at for a while,My Build a Truck project is ahead of it and with spring it is relegated down the list. If i sell my current shop gas station this year it will be a while before i get a replacement shop built and setup.

Robyn
05-01-2024, 06:04
Copy

At any rate....Box needs to come out and apart....

Yukon6.2
05-02-2024, 09:40
Peaking of projects...
I look forward to the return of the Franken Cat.