Trans/T-case flush during engine break in

[Kingarex]

So I've done some good searching, and have *almost* answered my question, but decided to post and make sure that my reasoning is sound.

I just finished a complete top and bottom end engine build. I'll be breaking in with Royal Purple break in oil this week. Clutch and flywheel are new, otherwise the trans/T-case/rear end are all stock with 136k on them.

I have redline products on order to run in my drivetrain long term, but the trans, and t-case were sitting in a dusty garage, unplugged (open axle holes) and I don't want to waste a good fluid on a (possibly) dirty system.

My question is, is there a cheap GL-4, or even conventional MTF that will be IN STOCK at napa or something that I can run for 500 miles to flush my components, then replace with redline when my shipment arrives? I don't see this being a problem, as the first 500 miles will be driven very gingerly and there will be little heat/stress on the powertrain. I just need a cheap fluid that will lube and then collect any particulates so I can drain and remove them prior to adding my MT-90.

 

[vr4joe]

I heard and did some research on Pennzoil Synchromesh. I know a lot of guys on this forum are running this in their trannys full time and can be bought at your local Napa/Autozone stores.

It's a lot cheaper than Redline MT90 and is proven for our brass metal parts within our transmissions. This fluid would be great for what you are looking for. I've even heard some people prefer this over Redline products.

 

[taz4432]

Run ATF through it under gentle driving around the block a few times. This will clean it out way better than any MTF ever can, and as an added bonus, will help clean up any old gunk as well.

After the short drive, come back, drain it, fill with MTF of choice and enjoy