Transmission on 89 XLT

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captsb890

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I had my transmission overhauled at AAMCO I know it takes a while for the computer to learn again and it drove ok--I noticed when I floored it that it didn't jump into passing gear-? I also noticed that when it started accelerating , it got up to a certain speed and high rpm and didn't shift to higher gear-just like it was trying as it was lurching but just couldn't do it--- What could it be-??
My 85 Bronco had a governor on it where it wouldn't go over 55-60 in those days---------Do you think this 89 has a governor---and if so how could you tell-?? with a 351/5.8 it should have plenty of snap.
A little advice here
 

Skitter302

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Sounds like the cable from the transmission to the throttle linkage is out of adjustment.
 
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captsb890

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Thanks for that----I called them and will bring it to them------So for clarification a transmission shifts with linkage input-? Or how does that work---someone said the computer shifts it by sensing rpm-?? The linkage makes more sense-------like I said it shifts really smooth at lower speeds it is the high end that has the problem--------
 

miesk5

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Yo Capt,
Which transmission do you have?
89 5.0 has AOD
89 5.8 has C6
Screenshot_20201030-102541.jpg

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AOD:
Screenshot_20201126-142300_Drive.jpg

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C6;
No Upshift at Wide-Open Throttle
  1. Vacuum modulator or rod malfunction.
  2. Check vacuum at modulator.
    Pull the vacuum line off the mod. If fluid comes out of the vacuum line your modulator is no good.
    Check vacuum line to modulator from engine intake manifold source.
    See Vacuum Gauge Diagnosis - BEST!; Normal engine; Steady gauge 18"-20" at all speeds..." READ MUCH MORE
    Source: by Craig U @ Reading your vacuum gauge

    Vacuum Modulator; The vacuum modulator is a vital component of an automatic transmission. It tells the transmission what kind of load is being put on it allowing the transmission to react with the proper line pressures and shift points. Over time, modulators can develop leaks, get ruptured diaphragms, get bent, etc. Not only can this cause annoying drivability issues, it can lead to premature transmission failure.

    Vacuum Modulator Adjustment; "...SOME Stock factory modulators are pre-set and most are sealed. TCI® StreetFighter® modulator-type transmissions are all equipped with adjustable modulators. By turning the adjusting ***** (found in the vacuum ******) counterclockwise, you will lower the spring pre-load. This will cause earlier shifts. By turning the adjusting ***** clockwise and raising the spring pre-load, the shift points will go up. The range of adjustability is only a few mph either way..."
    Source: by TCI Automotive tciauto.com via web.archive.org
    Source: by tciauto.com

    Also check for Vacuum leaks in HVAC system (to some doors), at PCV Valve, etc
    Source: by tciauto.com


    2. Also watch out that you don't loose the small removable pin in the end of the modulator, you need it for the new one. You will need to know the color band on the side of the modulator when you go to get a new one.
    by Seabronc RIP friend..
  3. Governor or fluid passage malfunction.
 

chrlsful

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C-6 - still it should respond as U mentioned. Report this to them, ck in w/BBB, the Chamber or others (not time for DA's office: Consumer Protection) but nice to have contact info in case of need. Speak nice, nice to them ("I'm no mechanic...can U help me understand...etc) but have a big stick in ur back pocket. Do Not pull it out (threaten, etc) but hold for when U might need it. If in a 2nd talk they back peddle...ask them for some sorta future date this thing will get resolved (stick to 2 wks max). U did pay, there isa grantee, and follow up w/the resources listed. Small clams court is for if it is broken. Try everything U can prior to this. U can never tell what a judge will decide (usually just 1/2 & 1/2 for each party). HTH, I imagine they will wrench onit, it will B wrkin again real soon...
 
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captsb890

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It was the linkage adjustment---they tweaked on it and it shifts good---kicks down in passing gear like a race horse coming out of the gate---as a matter of fact it is a little scary--it screams !
 
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captsb890

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Not a Bronco question but I have a 1985 Cargo star box truck and can't find the layout labeling of the fuse box---any leads would help---thanks
 

miesk5

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Yo captsb890,
Give them a bit more time.
At times it takes me a few days to gather info from some former Ford employees who have boxes of Info at home
 

chrlsful

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Not a Bronco question but I have a 1985 Cargo star box truck and can't find the layout labeling of the fuse box---any leads would help---thanks
Sounds like U need to start nother thread.
R U saying "Western Star Truck Co"? They usta B White Motor Co outta Portland. Its been Autocar, Volvo and MB (Dalmner). Find what era and ether go to this company or who was ownining it at the time of manafacturer. A new thread here could certainly assist (more than buttied here)!
 

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