Author Topic: transmission.  (Read 7217 times)

Offline 84chvy

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transmission.
« on: March 08, 2012, 07:00:13 pm »
so the transmission on my stepside is slipping a little bit. and when i got the truck behind the seat was a brand new transmission filter and gasket for the pan. so i was wondering if that will fix the slipping? it only slips a but when i put it it reverse it slips then it will catch on and sometimes in drive it will slip. so will the filter fix the slipping? and also, do you change the transmission fluid like oil, and when i do change it about how much will it hold? thanks in advance!

Offline Blazin

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Re: transmission.
« Reply #1 on: March 08, 2012, 09:01:19 pm »
Once an automatic transmission slips the only thing that fixes it is a rebuild.
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Offline Jason S

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Re: transmission.
« Reply #2 on: March 08, 2012, 09:25:15 pm »
You can try changing the fluid and filter and it may buy you some time.

Adding a little Berryman's B-12 into the transmission may help soften the seals a bit and extend the usefulness a little, but you're likely going to need a rebuild in the near future.

1973 GMC K2500, Super Custom, Camper Special, 350, TH350, NP203, 4.10's
1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

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Offline bake74

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Re: transmission.
« Reply #3 on: March 09, 2012, 06:10:00 am »
     The only way fluid in a auto transmission can cause slipping is after it has got so bad that the lubrication factors of the fluid have disappeared and started wearing out componets of the transmission like the valve body or such.
     When you drain the fluid you will be able to tell, if it got that bad it will be sludge looking.  When you go to change the filter, look at the valve body closely, sounds like you might just have some stuff built on in the passages in the valve body, if you don't see anything that stands out, then Blazin is right, you should consider a rebuild in the future.  Jason S is right also, by changing the fluid and servicing it thoroughly, you might buy some more time.
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Offline Blazin

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Re: transmission.
« Reply #4 on: March 09, 2012, 11:00:31 pm »
Or putting fresh fluid in it might finish it off. I have had that happen before. Bought a truck the trans worked perfectly. Drove it around for a week or two. Decided the trans fluid looked dirty. So I did a stroke of business and changed all the fluids in the truck. I didn't even get 2 miles down the road and the transmission blew lunch!
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline Donut

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Re: transmission.
« Reply #5 on: March 10, 2012, 04:32:06 am »
Plan for a rebuild, if it miraculously cures itself your $ ahead.

Did the same as Blazin, except my fluid looked good but I didn't know how old it was. (recent purchase)
Mile and a half, 3rd was gone.  Half mile beyond that, they were all gone.  Major meltdown.  Trans is now in the shed, 1/2 back together.  (never done one, so I'm a little slow)

Drove it to get gas the day before, and it was fine.  Then I changed the fluid.....  Co-incidence?  possibly.
Owned the truck for 4 mos and only put 12 mi. on it so far.
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Offline bake74

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Re: transmission.
« Reply #6 on: March 10, 2012, 05:37:58 am »
Or putting fresh fluid in it might finish it off. I have had that happen before. Bought a truck the trans worked perfectly. Drove it around for a week or two. Decided the trans fluid looked dirty. So I did a stroke of business and changed all the fluids in the truck. I didn't even get 2 miles down the road and the transmission blew lunch!

      WOW never had that happen, but can image that must have been frustrating.  If you can picture this, I would be so frustrated I would be on the side of the road probably kicking the side of the tires and then jumping up and down from hurting my foot.   ;D
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline Jason S

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Re: transmission.
« Reply #7 on: March 10, 2012, 01:38:14 pm »
Just for a little optimistic encouragement, I have experienced a slipping auto rise from its grave.

This was with a '98 Jeep Grand Cherokee 318 V8, automatic (I know it's not a Chevrolet or GMC)

I bought it with about 120K miles on it, the previous owner said the transmission was going out.  It'd go into drive and reverse but had great amounts of slippage and wouldn't upshift. 

I looked through the receipts that the previous owner provided.  They had changed the trans fluid at one time, but used Dexron/Mercon in the Chrysler transmission (Fail!).

I changed the filter and fluid,  refilled the transmission with the correct Chrysler ATF+3 fluid.  I started the engine, put it in drive. A little slipping. Took it for a drive, it slowly upshifted. The more I drove it, the better it began to operate.  I adjusted the bands and drove that thing for another 30K before I sold it. 
« Last Edit: March 10, 2012, 01:40:01 pm by Jason S »
1973 GMC K2500, Super Custom, Camper Special, 350, TH350, NP203, 4.10's
1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

"1) Peace through strength; 2) Trust but verify; 3) Beware of evil in the modern world"

Offline Blazin

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Re: transmission.
« Reply #8 on: March 10, 2012, 02:26:54 pm »
I know two other guys that have done the same as Donut, and I. Bought a new / used rig that the trans worked perfectly. Changed the fluid and within days it was toast. One was a Pontiac Tempest with a TH350, the other and F250 with a C6.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline thirsty

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Re: transmission.
« Reply #9 on: March 11, 2012, 02:53:30 pm »
I know two other guys that have done the same as Donut, and I. Bought a new / used rig that the trans worked perfectly. Changed the fluid and within days it was toast.
I have seen this before in the past also. I always got junkyard transmissions when needed. Put them in to make sure they worked then changed the fluid and filter only to loose the tranny shortly after. I started to just put them in and run them and had better luck.
Probably was just coincidence but it happened to me on a couple different flavors of vehicles.
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Offline 84chvy

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Re: transmission.
« Reply #10 on: March 11, 2012, 10:17:33 pm »
whats a used th350 cost or a rebuilt for the one i have?

Offline nlauffer

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Re: transmission.
« Reply #11 on: March 11, 2012, 10:29:05 pm »
I just had trans issues.  It ended up being the modulator valve.  Not same probably, but I checked on a rebuilt one at a shop around here that has done a 5 spd and a front wheel drive trans for me.  The price was &350-$400.  I asked about making adjustments for more clutches and the price was the same.  At that price, you might as well just get it done.

Offline Blazin

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Re: transmission.
« Reply #12 on: March 12, 2012, 04:15:05 pm »
Rebuilt in my neck of the woods is anywhere from $700 - $1,000.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline jaredts

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Re: transmission.
« Reply #13 on: March 12, 2012, 08:24:24 pm »
Used th350's are plentiful and they seem to hold up well.  Maybe $300 or less.

Offline 87454westernhauler

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Re: transmission.
« Reply #14 on: March 12, 2012, 08:59:46 pm »
my 74 cost 700 to have the trans completely rebuilt and gone through and they pulled and instaled it. i just bought a used low milege 700r4 for a 89 i had from my local junk yard for 200 and they pulled it and gave me a 30 day warantly on it.
86 c10 350 sbc 700R4 Daily Driver
79 gmc c20 350 th350
78 k1500 4x4 350 th350