What are the opinions of the assembled masses about flush versus drain and fill? In case it matters, it’s a newly purchased 1993 Buick Roadmaster, 138k, with fluids that look “used” but not terrible. No tranny symptoms, etc. May have a stuck open thermostat.
If you are talking the RADIATOR I would have a thorough flush on a vehicle that age, especially if the coolant looks used up.
In addition, you need a pressure check test and may need some new hoses, as well as a new thermostat. Once you do all that you’re set for the next 5 years or so.
Tranny or radiator fluids?
I refer to both the cooling system and the transmission.
@merlot If you are going to flush a transmission you should also drain, change the FILTER and fill. Ordinarily I would not flush only; it will distribute all sot of contaminants into areas where they should not be. And the old filter will still be in there.
Flushing alone at a typical shop will almost guarantee transmission failure within a year.
Take it to a specialist INDEPENDENT transmission shop and for $140 or so they will do all the right things, like changing the fluid AND the filter.
A typical radiator shop will not be equipped to do proper transmission work. You need two different shops!!!
Drop transmission pan, clean it, replace the filter, fresh gasket and fluid
Drain and refill radiator and block. If in doubt, CAREFULLY hose out the radiator with a hose. Change out the thermostat and cap
Done 
Merlot is a wine.
@melott Sorry. I make wine and Merlot, Pinot Noir, and Cabernet Sauvignon are my best reds. I also make a Chateau Neuf du Pape under my own label.
Try making Melott wine.
So, of course the tranny filter will be replaced. But it doesn’t seem like anyone thinks the extra expense of a flush is worthwhile there.
@melott Agree. I’ve always done just the drain and filter routine every 40,000 -50,000 miles, and have only had one $175 transmission repair (in 1976) since 1965. If the unit is really gunked up the posters here would recommend a drain & filter, followed by another one 10,000 miles later. That would get nearly all the contaminants out.
Those flushing machines in the hands of a novice can do a lot of damage.
Flush a radiator by all means but never flush a transmission.
When servicing an automatic transmission it’s critical to clean the inside of the pan of all gunk and debris, so it shines like new, and to replace the transmission filter. If the shop wants to use the flushing machine to replace the fluid, that should work ok as long as they use the correct fluid for your transmission. With the pan removed, that’s a good time for the shop to inspect for any metal debris too. Ask them to be sure to sieve the removed fluid, visually checking for bits of metal.
Thread hijack @Docnick Been brewing my own beer, rolling my own cigs, and looking into wine, can I tap on your expertice somewhere?
My opinion: On an old car that you don’t know the maintenance history of, I wouldn’t do a Tranny flush. You are asking for it. I would drive it till warm, then drain the fluid (no drain plug, you’ve got to drop the pan). Clean the pan, new gasket, filter and fluid.
@Barkydog Winemaking has become quite easy with the advent of ready made wine kits. These typically are sold by specialist stores, although Costco sells them on line as well. Expect to pay about $65 at Costco for a kit that makes 30 bottles. Avoid the cheaper kits sold at Walmart.
It’s important to buy good kits that are real grape juice with no added sugar. This give the real flavor once the wine is made.
Just follow the instructions EXACTLY!
The fermenting should take place at room temperature or slightly above. Cleanliness is very important since stray bacteria will multiply during the fermenting process and will cause off flavors. Once the wine is fermented with the right amount of alcohol we let it sit in the basement for up to 6 months to get all the sediment to settle on the bottom of the carboy. Then we bottle it. We don’t filter after the 6 months; filtering is messy and you may lose some flavor.
The kit instructions will say 6 weeks, but you can ignore that. Oxygen is the biggest enemy of wine so the carboy must have an airlock.
We have a wine cellar that is very cool all year round. Wine is best stored in a cool, dark place.
We’ve had good kits from California, France, Australia and Chile.
So, of course the tranny filter will be replaced. But it doesn’t seem like anyone thinks the extra expense of a flush is worthwhile there. <<<
It’s not the expense. It’s the idea that, with an old automatic tranny that has gone a long time (if ever) without a fluid change, there might be a lot of guck in there. The theory is, if you do a flush it will knock a lot of that grunge loose and clog some of the many holes/passages in a modern tranny. In that situation (in my opinion) it’s better to just drain and fill/filter so as to not knock loose the “bad” stuff. Then cross your fingers.
I think this guy wants to keep us “on the straight and narrow” :trollface:
Sure seems to making friends quickly . . . implying that one regular MIGHT be a troll while flagging another regular’s post as spam
For the most part, we’re here to provide advice, ask questions and have an enjoyable time
please don’t ruin it
Maybe someone needs to drink a glass of merlot and chill.
Just to keep it automotive: don’t drink and drive.
@melott formerly known as merlot Can’t see who flags stuff, If it was you flagging I apologize for hijack, but inquiring minds want to know. Sure off base, sure out of car talk rules, Now to keep it car related I predict the next gen of cars go with wine names, the cabernet, the merlot, the reisling, the mad dog, ha ha.
I did not flag anything.