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Discussion Starter · #1 ·
My 1990 Troopers kicks when shifting to 4th gear and a buddy said to try using Marvel Mystery Oil when doing a tranny oil change and should help ease the changing of gears.

Has anybody tried using this Oil before and if you did what kind of results did you have?
 

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ive used this stuff in aircraft engines to free sticky valves, usually works for that. Its worth a try, people swear by it in their old British cars.
 

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let me know if it helps, i might pour some in my transmission.
 

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Discussion Starter · #4 ·
yes I'm scared to damage tranny but my trooper tops off at 80mph ( when it could hit 95) and usually stays in at 3000rpm but it bucks pretty hard when gettin to fourth and then coming back to 3rd, I'm afraid its just warning signs for a dying tranny

buddy says it might be a governator? to regulate speed up to 75mph? is there such a thing?
 

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is it a manual or an auto?
 

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AFAIK - NO Isuzu has a governor - unless you stole yours off a ride at Disneyland.

There is however, a real Governator::



BUT anyway --------

4th gear hard-hits are usually a pressure control problem. Since 4th is in the front section of the unit, it may show something like a thrust washer in the pan if you're so inclined to look there.

When the input shaft 'floats' and it's position isn't controlled, this is the problem: hard hitting and possibly delayed 4th gear.

BTW: Marvel won't fix this. It's good for a lot of things, but it cannot replace a thrust washer or re-round a hogged out annular seal surface.
 

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Naldo87GA said:
My 1990 Troopers kicks when shifting to 4th gear and a buddy said to try using Marvel Mystery Oil when doing a tranny oil change and should help ease the changing of gears.

Has anybody tried using this Oil before and if you did what kind of results did you have?
If its an automatic,adding crazy stuff to your tranny is a recipe for disaster.
 

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Amazed again because people actually believe that clutches gently apply during a gear change.

A clutch pack application is solid, no spinning-slipping-hesitation or they'd only make the application a couple of times before the untlt needed a rebuild.

There is NO slippage or gentle friction material application - in ANY gear/shift/clutch pack. Period.

All the shock of the shift is taken up but the torque convertor, and if it doesn't release (eg: the TCC) then you'll lose teeth and get a whiplash every shift.

So --- adding a magic ingredient to soften a shift - especially just one of them - is foolish to think and foolish-er to attempt with additives.

However - I have used Marvel to assemble valve bodies from time to time when the unit won't be put into service for a while - as in building a bench unit for later installation.
 

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Discussion Starter · #9 ·
@Surfer Joe

thanks for clarifying my my wrong use of Governator lmao I'm sure that guy would know how to fix my Isuzu

Since I know diddly squat about cars, I figured the mystery oil would do just that, ease the shift of 3rd in to 4th

My car is AUTOmatic with 194k

so when you say it floats, can this be corrected or is it an engine problem that will worsen over time?

thanks for all the info!
 

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Transmission problems are related to the engine by conditions that are not inn evidence here,

The 'float' is in the input shaft inside th transmission. It is the first driven part beyond the torque convertor and the 'float' is that shaft wandering front to back prolly less that 1.16th of an inch, but enough to dump pressure and fluid into a void, keeping the TCC applied during the shift.

No - this is an internal problem repaired by a rebuild and by now, the replacement of a few more than normal hard parts.

HOWEVER - get it diagnosed first as this MIGHT be a TCC control problem and not much else. Don't count on it though.
 

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Having owned a British car for several years, and having owned several cars over 100K miles and having used Marvelous Mystery Oil and Seafoam, I'd use Seafoam Transtune over MMO.

Both of these are detergent products, and I don't like using a lot of them. I have some friends with a tire shop and used car lot and they told me they run Seafoam Transtune in all of their vehicles and all the cars on their lot.

I'd also ask how long its been since you've serviced the transmission (fluid and filter)? If your a little low on fluid, topping off with some transtune would be what I would start with (I've got some in mine) and run it for a couple thousand miles then do a fluid & filter change. I don't have a problem adding it, but I would always want to do a filter change soon afterward.
 

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AudioRedneck said:
Having owned a British car for several years, and having owned several cars over 100K miles and having used Marvelous Mystery Oil and Seafoam, I'd use Seafoam Transtune over MMO.

Both of these are detergent products, and I don't like using a lot of them. I have some friends with a tire shop and used car lot and they told me they run Seafoam Transtune in all of their vehicles and all the cars on their lot.

I'd also ask how long its been since you've serviced the transmission (fluid and filter)? If your a little low on fluid, topping off with some transtune would be what I would start with (I've got some in mine) and run it for a couple thousand miles then do a fluid & filter change. I don't have a problem adding it, but I would always want to do a filter change soon afterward.
One problem I see is that you add it,thinking that your just going to add it for a while then change it out,but really,you cant change it out. You drain whats in the pan and dilute it ,but there is still the fluid in the torque convertor. The additives are going to be in there for a long time.
 

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mallen said:
One problem I see is that you add it,thinking that your just going to add it for a while then change it out,but really,you cant change it out. You drain whats in the pan and dilute it ,but there is still the fluid in the torque convertor. The additives are going to be in there for a long time.
I agree to a point. What I should have stressed is that when you first add it you are likely to get more gunk in your filter and that it is important to change it out. Leaving this stuff in is not a problem as it is basically just a different formula of transmission fluid (I've had my suspicions that MMO is also not far from ATF. I've used ATF to de-sludge an engine before and was happy with the results, and MMO and ATF look and feel suspiciously similar except MMO is a little thinner).

But the point is that when you add the stuff you are likely to clog the filter if it has not been changed in a while. I don't anything is going to "fix" a problem if it in the metal, though some additives may boost the capabilities of the fluids if the machine parts have some less than excessive wear.
 
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